Teĥum Shabbat / General Principles of Teĥum Shabbat

The need to travel from place to place stems from man’s deficiency: he cannot find his livelihood and meet his needs by remaining stationary. So he must roam and leave his place. But the idea of Shabbat is for every Jew to rest from his travails and worries, contemplate the inner perfection of creation, thank God for choosing Israel from all peoples and giving us His Torah, and delight in God and His goodness.

For this reason, the Sages ordained boundaries (teḥumin) within which one may walk on Shabbat, and beyond which one may not walk. One’s teḥum Shabbat (Shabbat boundary) is determined by his mekom shevita – the place where he is spending Shabbat (literally “stopping place”) – plus 2,000 amot in each direction (2,000 amot corresponds to 2,000 steps of an average person, approximately 912 m).¹

footnotes: ¹ . According to R. Ḥayim Naeh’s calculations, which are based on Rambam (with whom the vast majority of poskim agree), one ama is 48 cm, and 2,000 amot is 960 m. According to Ḥazon Ish, one ama is 57.6 cm, and 2,000 amot is 1152 m. Since it has been ascertained that the Turkish dirhem with which R. Naeh was familiar is larger than the dirhem used in Rambam’s time, we should follow the more accurate calculation even though it results in a stringency. (Additionally, the shi’urim of volume need to be in sync with the shi’urim of distance, since the Sages said that the volume of forty se’ah can fit into an area of one ama by one ama by three amot.) Therefore, R. Ḥayim Beinish writes in Midot Ve-shi’urei Torah 5:24 that according to Rambam, one ama is 45.6 cm and 2,000 amot is 912 m. In addition, the actual length of the average man’s forearm (ama) is approximately 45 cm. See Peninei Halakha:Berakhot, ch. 10 n. 11. This is how we present every halakhic measurement. See above, ch. 29 n. 1.

If one is spending Shabbat in a field (i.e., not in a city or town), his mekom shevita is defined as four amot squared. This is the amount of space one occupies when lying on the ground with his arms and legs outstretched.² He may walk 2,000 amot beyond that in each direction. If he is spending Shabbat in a city or town, the entire settled area is considered one place, and he may travel 2,000 amot beyond the city limits (see section 8 below).

footnotes: ² . According to SA 396:1, one’s “place” is four amot by four amot, as it is with regard to carrying in a reshut ha-rabim or a karmelit. Rema writes that some maintain for the purposes of teḥumin, one’s place extends four amot from the center in each direction, for a total of eight amot by eight amot.

According to Rambam and Smag, teḥum Shabbat restrictions are based on Torah law, though the Torah prohibition forbids one to travel more than twelve mil (24,000 amot, which is 10944 m, almost eleven km) from his mekom shevita. This is based on the size of the Israelite camp in the wilderness, as the Torah states: “Let everyone remain where he is; let no man leave his place on the seventh day” (Shemot 16:29). However, according to Ramban, Rosh, Rashba, and most Rishonim, this verse does not refer to the laws of teḥum but rather to those of carrying in a reshut ha-rabim; all boundary restrictions (even beyond twelve mil) are rabbinic law.³

footnotes: ³ The Sages were uncertain whether boundary restrictions apply above ten tefaḥim; perhaps, since people do not walk there, the prohibition does not apply there. In practice, when there is uncertainty pertaining to a rabbinic prohibition, the law follows the more lenient position. Therefore, regarding boat travel in oceans and rivers, where Rambam agrees that the prohibition is not a Torah prohibition (as such travel is not comparable to travel in the wilderness), as long as one is ten tefaḥim above the seabed, the teḥum prohibitions do not apply (Eruvin 43a; SA 404:1). According to SA 248:2, the ten tefaḥim above the seabed are measured from the bottom of the boat, while according to R. Eliezer of Metz they are measured from one’s feet. SAH and MB 248:14 state that in times of need one may be lenient. However, if one is traveling at a height of more than ten tefaḥim above land, several poskim maintain that one should be stringent in accordance with Rambam and not travel more than twelve mil (Rema 404:1).

The Sages ordained that if one must travel beyond the teḥum on Shabbat – in order to attend a wedding celebration or a Torah lecture – he may make an eruv teḥumin, which extends his teḥum in the necessary direction (as explained below in sections 12-14). One who leaves his teḥum forfeits it and must remain within his four amot (as explained below, section 11).

Teĥum Shabbat / Squaring the Teĥum

The Sages established that one’s mekom shevita on Shabbat is square, and thus his teḥum is square as well. This means that if he is spending Shabbat in a field, and his mekom shevita is thus four amot, the measurement is not made by drawing a circle around him with a diameter of four amot. Rather, to determine his mekom shevita we inscribe such a circle in a square with four-ama sides along the four cardinal directions, which adds space to his mekom shevita at the corners. Similarly, if one’s mekom shevita is in a city or town, even if the area is round, we inscribe it in a square or rectangle, adding space at the corners (m. Eruvin 53a).

Then 2,000 amot are measured in each direction. Once again we draw a square or rectangle, which once again grants him additional space in the corners.⁴

footnotes: ⁴ When measuring 2,000 amot from a city or town, according to Rambam and SA 398:5, we measure from the outermost homes or from the eruv (following the opinion of the Sages in Eruvin 57a). According to Rosh and Rema, one first adds the equivalent area of a karpif (an enclosed courtyard in front of the houses) to the city, which amounts to 70 2/3 amot (approximately 32 meters). This area is now considered part of the city. From there we measure 2,000 amot (following the opinion of R. Meir in the above gemara; see MB 398:21 and BHL s.v. “ve-khen”). As explained in section 8 below, when there are two settled areas adjacent to each other, SA agrees to the karpif rule.

This rule, that we square off the city, is derived from the Torah’s description of the area the Levites were given outside each of their cities: You shall measure off two thousand amot outside the city wall all around. You shall measure off two thousand amot outside the town on the east side (lit. corner; same applies to the other directions), two thousand on the south side, two thousand on the west side, and two thousand on the north side, with the city in the center. (Bamidbar 35:5)

The most straightforward explanation for why we square the teḥum is that it is extremely difficult to measure and mark off a circular boundary. One would need to measure 2,000 amot from almost each and every point of the city’s perimeter. In contrast, when marking off a square boundary, only four measurements need to be made – one in each of the four cardinal directions. After that, a straight line can be drawn in each direction, and the result is the teḥum.

Additionally, this method reflects a spiritual reality. A circle represents the infinite, which has no beginning and no end. A person’s life is circular and cyclical. His actions, wishes, and thoughts repeat themselves cyclically. Even his limbs are circular and cylindrical. This makes it difficult for a person to realize his aspirations. The way to solve the problem is to take one’s “circular” infinite ideas, and give them a “square” finite framework that will help him put them into practice. This is the meaning of teḥum Shabbat, which is meant to provide a framework for absorbing the holiness and blessing of Shabbat. This is why each city belonging to the Levites, who are charged with revealing faith in this world, is surrounded by a square boundary.

Teĥum Shabbat / Teĥum Shabbat Is Individual

Teḥum Shabbat is specific to every individual, based on his location. For example, let us say that the homes of two neighbors (who do not live in a city) are located 1,000 amot apart from each other. Each neighbor has his own teḥum Shabbat, part of which overlaps with his neighbor’s teḥum Shabbat, and part of which does not.

The laws of teḥumin apply to one’s animals and belongings, and to Jews as well as non-Jews (see n, 12 below). Therefore, if one carried his talit to the edge of his teḥum, and his friend wants to borrow it but has a different teḥum, the friend may not carry the talit beyond its owner’s teḥum (SA 397:3).

If the talit is jointly owned, it may be carried only where their teḥumin overlap (ibid., 397:9).

Teĥum Shabbat / Spending Shabbat In or Outside a City

For someone who is spending Shabbat in a city or town, whether its residents are Jewish or non-Jewish, the whole area that is built up contiguously is considered one place, and the 2,000 amot of the teḥum are measured from its perimeter. Even if there is space between the homes, as long as they are surrounded by a fence or an eruv, the entire enclosed area is considered one place, and the 2,000 amot are measured from its perimeter (as will be explained in section 8).

All this pertains to one who spends Shabbat in the city or within its squared-off area. However, one who spends Shabbat in a field near the city is limited to 2,000 amot in each direction, and if his 2,000 amot terminate inside a city, his teḥum ends right there, in the middle of the city. We do not consider the whole city his four amot.⁵

footnotes: ⁵ If a town is so small that the entire area is within his 2,000 amot, then the area of the town is skipped (the whole city is considered four amot), and his 2,000 amot continue from the far edge of the town (SA 408:1). Here is an example:

Teĥum Shabbat / Measuring Teĥum in Rabbinic Times and Nowadays

The Sages established rules for measuring the teḥum Shabbat as precisely as possible. First, they declared: “Teḥum Shabbat may be measured only with a rope that is fifty amot long, no more or less” (Eruvin 57b). If a longer rope were used, its weight would make it hard to pull taut, and the resulting measurement would be too short. If a shorter rope were used, one might pull it too tight, and the resulting measurement would be too long. Second, they required those measuring to hold the rope at chest height. If the person holding one end of the rope were to hold it at head level, while the person at the other end were to hold it at foot level, the resulting measurement would be too short (SA 399:1-3). Third, they said that when measuring an area that contains a valley, one person should stand on either side of the valley, so that they can measure the distance in the air. When measuring an area that contains a hill, tall poles should be set up so that the rope stretches above the hill. If the valley or hill is more than fifty amot wide, thus making it impossible to use a fifty-ama rope, the area should be measured with a four-ama rope. The person standing above should hold the rope at foot level, and the person standing below should hold it at chest level. If the slope is so steep that it would be difficult to calculate the measurement this way, the measurement should be estimated. If the area contains a cliff, as long as the cliff is less than four amot wide, it is not taken into account at all (Eruvin 58a-b; SA 399:4-5).

The Sages added that for these measurements, we rely only on an expert who knows how to calculate distances properly. If two experts arrive at different measurements, we follow the measurement that results in a larger teḥum. Since the laws of teḥum are rabbinic, we follow the more lenient opinion (Eruvin 58b-59a; SA 399:7-9). If one happens to spend Shabbat in a place where teḥum Shabbat has not been calculated, and he needs to go somewhere for the sake of a mitzva, he may take 2,000 medium-sized strides, which is approximately 2,000 amot (Eruvin 42a; SA 397:2; MB ad loc. 5).

Today it is best to establish teḥum Shabbat using aerial maps or GPS devices, as these can measure distances with extreme precision. We should not insist on measuring in the way that the Sages established. After all, their whole purpose was to measure as precisely as possible, using the tools available to them, without terribly inconveniencing those charged with measuring. Now that we have methods of measuring that are both more precise and more convenient, we must take advantage of them.

Teĥum Shabbat / The Cardinal Directions and Squaring a City

As we have seen (section 2), we square a person’s mekom shevita to determine his teḥum. If he is in a field (i.e., not in a city or town), his mekom shevita is a square with four-ama sides; if he is in a city, we inscribe the city in a square. From this square we measure 2,000 amot in each direction.

Let us add now that when we square the city, we do so based on the four cardinal directions (SA 398:3).⁶ If the city already has corners that lend themselves to squaring in a way that does not follow the four cardinal directions, the squaring is done accordingly (SA 398:1).

footnotes: ⁶ . The city’s residents may not decide to square the city in a way that does not follow the four cardinal directions just because they would like to add space in the corners in the direction they wish to go. This is because the law is unequivocal: the city must be squared in accordance with the four cardinal directions. This is based upon the procedure described for the Levite cities: “You shall measure off two thousand amot outside the city wall all around. You shall measure off two thousand amot outside the city on the east side, two thousand on the south side, two thousand on the west side, and two thousand on the north side, with the city in the center” (Bamidbar 35:5). We see that the verse follows the four cardinal directions. This understanding is implied in MT 28:7 and SA 398:3, and is also followed by MB 398:7 and Ḥazon Ish 110:23. Some maintain that the city’s residents do have the right to decide to square their city in a way that does not correspond with the four cardinal directions. In such a case, every individual is bound by the group’s decision (Rabbeinu Yehonatan, Eruvin 16a, s.v. “im”; Perisha 398:1; Mirkevet Ha-Mishneh, Shabbat 27:2; Noda Bi-Yehuda Mahadura Tinyana, OḤ 51).

Examples of squaring based on the four cardinal directions:

Examples in which it is agreed that the squaring does not follow the four cardinal directions:

When a city’s shape lends itself to squaring that does not correspond to the four cardinal directions, the poskim disagree how to square it. Some maintain that only when there is a compelling reason not to follow the four cardinal directions may one follow the layout of the city (SAH 398:3; Ḥayei Adam 76:14). However, most poskim maintain that if the shape of a city clearly lends itself to squaring in a certain way, we follow this squaring even though it does not correspond to the four cardinal directions (see n. 7). In cases of doubt, the local rabbinate or rabbinic authority should make the decision.

Examples of such intermediate cases in which a city’s shape clearly lends itself to squaring in a direction other than the four cardinal directions include cases where one side of the city is straight from one end of the city to the other (figure 1) and cases where the perimeter of the city contains a right angle (figure 2, in which case we follow the directions of the right angle and not the four cardinal directions).⁷

footnotes: ⁷ In the city featured in figure 1, most Rishonim and Aḥaronim rule that it is squared based on the right angle (as is the case with a city that is shaped like an L, according to Rashba, Ran, Ritva, and Me’iri). In the city featured in figure 2, one side of the entire city is a straight line. The law in such a case can be derived from the case of a city that is shaped like a bow (section 7), where it is squared based on this straight line, or “bowstring” (Me’iri, Eruvin 55a). Ḥazon Ish states this as well in OḤ 80 and 110. Some maintain that in both the above cases, the city must be squared based on the four cardinal directions (SAH 388:3; Ḥayei Adam 76:14). Others maintain that in all doubtful cases, the city is squared in whichever way will add the least area to the city (Ḥazon Ish 110:23). The halakha follows the first opinion, that of the majority of poskim, and the figures above reflect this opinion. Nevertheless, when it is not clear if the perimeter of a city contains a right angle, the local rabbinate or rabbinic authority may decide to rely on those who rule that such a city should be squared based on the four cardinal directions.

It is important to note that if one is spending Shabbat outside a city and his mekom shevita is limited to four amot square, he may choose to square his mekom shevita in whatever direction he wishes, and this will also determine how his 2,000-ama teḥum is squared (see section 12 below).

Teĥum Shabbat / Cases In Which We Do Not Square a City

As we have seen, by squaring the city, we add space in the corners to the teḥum. However, the Sages pointed out that sometimes we cannot draw straight lines to square the whole city, because the resulting square would include uninhabited areas that are too large to be considered subsumed by the city. Examples of this would be cities that are shaped like a bow or like an L. The operative principle is that if there are 4,000 amot between the two ends of the shape, that part of the city cannot be squared.

An L-shaped city:

A bow-shaped city:⁸

footnotes: ⁸ Rambam and SA 388:4 state, in disagreement with this diagram, that the 2,000 amot are measured from the edges of the inhabited homes. The resulting teḥum follows the curve of the bow. However, the diagram follows the opinion of Tosafot (55b, s.v. “ve-im lav”), Rosh, most Rishonim, and Rema that for the inside of the bow, where the arc narrows to less than 4,000 amot, we draw a “bowstring” from one end of the arc to the other and measure the teḥum as 2,000 amot from that straight line (see diagram). The halakha follows the majority of poskim, especially since the laws of teḥumin are rabbinic, so the halakha follows the lenient position. Although Tur has an even more lenient opinion, the rest of the poskim disagree, as detailed in BHL s.v. “ve-yesh omrim.” Uncertainty still remains regarding how to measure the teḥum for the rest of the bow, where the arc widens to 4,000 amot and greater. It would seem that we can follow the position of Rambam and SA that the teḥum follows the curve, as displayed in the diagram. Ḥazon Ish maintains this as well (OḤ 110:10). See Harḥavot

Teĥum Shabbat / Connecting Settled Areas

As long as the houses in a city are contiguous, meaning that they are not farther away from one another than the size of a karpif (a large courtyard, approximately 32 m long), they are considered part of one area for the purpose of assessing the teḥum. If they are separated from one another by more space than that, they are not considered part of one area, and each house’s teḥum Shabbat is then calculated separately.⁹

footnotes: ⁹ The shi’ur of a karpif is 70 amot and four tefaḥim. Following the updated calculation described in n. 1, this is 32.224 m, and the size of two large courtyards is 64.448 m. For the sake of simplification, we use the rounded-off measurements of 32 m and 64 m.

If the houses in a city are contiguous, then even if one house is out of alignment, as long as it is not more than 32 m from the next house, the teḥum’s square or rectangle expands to include the unaligned house. If there are additional houses after this one, the teḥum expands to include them as well; this can continue even if it means that the teḥum extends outside the city proper for a distance that would take days to walk. As long as each house is not separated from the next by more than 32 m, the teḥum extends to include them. However, if a house is more than 32 m away, it is not included within the rectangle.

If the distance between two adjacent neighborhoods is greater than the size of two large courtyards (i.e., over 64 m), then each neighborhood is considered a town in its own right. We square each on its own, and then 2,000 amot are measured in each direction from that square. In contrast, if the distance separating the two neighborhoods is 64 m or less, they are considered one area and we square them together. There must be at least fifty residents living in an area for a group of houses to be defined as a neighborhood (Eruvin 60a). Even if there are fewer than fifty people, as long as the area contains three courtyards, each of which joins two homes together, or six homes, each of which has a courtyard, the area is still considered a neighborhood (MB 398:38; Ḥazon Ish OḤ 110:19).

If an area is enclosed by a wall or an eruv, all its homes and neighborhoods are considered one area. This is true even when the wall or eruv is farther than a karpif’s length from the last house, and even if there is a large distance between the homes and neighborhoods.

Teĥum Shabbat / Overlapping Squares

When the squares or rectangles formed around two cities overlap, even when there is no joint eruv, the overlapping area connects the cities. We draw a new rectangle around the entire area to include both cities. The residents of both cities may then walk 2,000 amot beyond the joint rectangle.

However, if the distance separating the corners of the two rectangles is greater than 4,000 amot, as we have seen (section 7), we do not square the entire area. Rather, each city is assigned a standard teḥum of 2,000 amot beyond its rectangle in each direction.

Teĥum Shabbat / The Status of Large Cities

If a highway within a city is more than 64 m wide and bisects the entire city, then the city is viewed as divided in two, and the teḥum Shabbat for residents of each of the two sections is calculated separately. This is also the case for a wide-open area such as a park or large garden. If it is more than 64 m wide and bisects the entire city, then the city is viewed as divided in two, and the teḥum Shabbat for each of the two sections is calculated separately.

At first glance, it would seem that the Ayalon Highway divides Tel Aviv into two cities. Nevertheless, since there is an eruv that encompasses all of Tel Aviv and the nearby cities, the eruv unites the different sections. Additionally, if a highway bisects a city but the rectangles drawn around each section overlap, then the overlapping area joins together the sections and we draw a new rectangle around the entire area, as explained above. Additionally, one could argue that since it is intended that all a city’s residents will make use of a highway, park, or large garden, they are considered part of the city and do not actually divide it.

Others disagree, maintaining that these factors – an eruv, usage by all city residents, and overlapping rectangles – cannot join together the two sections formed by a highway or park that bisects a city. The primary position is the lenient one. However, it is proper to be stringent and avoid walking more than twelve mil beyond the highway, since some say that traveling beyond twelve mil is forbidden by Torah law (see section 1 above).¹⁰

footnotes: ¹⁰ As mentioned above, two cities or neighborhoods do not join together if they are separated by 64 m, which is double the size of a city’s outskirts (SA 398:7). Rema adds that if the entire length of a city is bisected with at least this much space, then the city is viewed as divided in two. Similarly, if a park that is more than 64 m wide stretches the entire length of a city, it divides the city, and each part is considered its own city. R. Ephraim Ariel Buchwald in his book Kiryat Ariel presents a ruling of R. Yosef Shalom Elyashiv that the Ayalon Highway, Namir Highway (north of the Yarkon River), and the Yarkon itself – each of which is over 64 m wide – divide Tel Aviv into five cities.Nevertheless, for several reasons it seems that these highways and the river do not divide the city. First of all, the Tel Aviv eruv encloses all these parts, joining them together into one city. When the halakha speaks of a bisected city being divided in two, it is referring to a situation in which the walls have been breached. If the city is walled, however, it is still considered one area. Furthermore, even if the eruv happens to be down and in practice one may not carry in the area, as long as the majority of the eruv is still standing, the city may still be considered one area. Orḥot Shabbat states this in ch. 28 n. 163 in the name of R. Shmuel Auerbach, who derives it from the laws of sacrifices (certain types of which had to be eaten within the walls of Jerusalem), for which a wall whose breaches cover less length than its standing parts is effective (Tosafot, BM 53b).If the road bisecting a city is not straight, the rectangles drawn around each section can overlap, thus uniting the city even if there is no eruv. This opinion was expressed by R. Shalom Noaḥ Segal Weiss in Tikun Eruvin 2:5:39 (p. 211) and n. 156 (pp. 236-237). Maḥazeh Avraham OḤ 70 states that even if the rectangles do not touch each other, as long as the distance between them is less than 64 m, they are considered joined.Another justification for leniency is that the shi’ur of 64 m – double the size of a city’s outskirts – was based on the standards in talmudic times. However, now that cities are much more sprawling, the entire area that serves the city’s residents should be considered part of the city’s outskirts. This can be derived from the law of a city that is situated next to a stream. If the bank of the stream that is closer to the city has a balcony that is four amot wide, the entire stream is considered part of the city, and the city’s teḥum is measured from the farther bank. This would seem to be the case even when the width of the stream is greater than 64 m. MB 398:46 cites Ritva (Eruvin 61a, s.v. “ve-Ra”Ḥ z”l”) that since “this stream is in front of the whole city and is fit to be used by all the city’s residents, we can consider it an extension of the city even though it is not habitable.” We may also add the possibility raised by MA (398:13) that from the status of the stream we can extrapolate to any place that the city residents use. If so, urban highways are a part of the city even if they are very wide, since their purpose is to be used by the city’s residents. This would also be the case with public parks and gardens. R. Michael Bleicher writes along these lines in Teḥum Shabbat U-medidato, p. 24. (Nevertheless, we see from Rema, cited at the beginning of this note, that the definition of a city is based on physical criteria, not on whether the two sections share a municipality.)In practice, since the law is rabbinic, we may be lenient, whether based on the rationale that the city has an eruv, or on the rationale that the rectangles drawn around each section overlap. Each rationale is sufficient on its own, and they are even stronger when considered together. Even when distances greater than twelve mil are involved, where some Rishonim maintain that a Torah prohibition applies, we may be lenient based on these rationales. However, if there is no great need, it is proper to defer to the stringent opinion.

Teĥum Shabbat / Traveling Beyond the Teĥum and Items Arriving from Beyond the Teĥum

One who traveled beyond the boundaries of the teḥum, whether knowingly or unknowingly, forfeits his 2,000 amot and may now only move within his four amot (SA 405:1; n. 1 above). Should he need to move his bowels, he may walk to a place where he will be able do so privately. Afterward, he may distance himself from this place enough to avoid the foul smell, so that he may recite prayers and berakhot, but he may not move more than four amot from that spot (SA 406:1).

One who traveled beyond the teḥum knowingly and reached an area enclosed by a wall or eruv is nonetheless limited to his four amot. Even if he is now inside a house, he may not move more than four amot. In contrast, if he traveled beyond the teḥum unknowingly or under duress, he may walk freely within the enclosed area (SA 405:6; BHL s.v. “aval”).

If one traveled beyond the teḥum in order to save a life, the Sages ordained that upon completing his mission, he may walk 2,000 amot in each direction. If this new teḥum overlaps his original teḥum, he may return home, and he retains his original teḥum as though he never left (Eruvin 44b). In certain cases he may even return to his original place regardless of teḥumin, as explained above in 27:10 and n. 12).

If one is traveling on a plane that, due to unforeseen circumstances, lands in an airport on Shabbat, his teḥum Shabbat is established upon his landing, and he may not go farther than 2,000 amot in any direction.¹¹ Since an airport is generally surrounded by a fence and often contains an area for sleeping, the whole airport is considered his four amot, and he can walk another 2,000 amot beyond it. However, if the airport is not surrounded by a fence, then his mekom shevita is established the moment the plane touches down. If the plane then taxies on the runway for another 2,000 amot, he has gone beyond his teḥum, and he may not move any farther than his four amot. This means he must remain on the plane until Shabbat ends. If the crew or security personnel insist that he leave, or if he needs to leave in order to use the bathroom, he may do so. If he then reaches an enclosed area, he may move around within it, since the only reason he originally traveled beyond his teḥum is that he was forced to do so (SA 405:6). If his flight was for the sake of a mitzva, then even if the plane taxies for a full kilometer and the airport is not fenced in, he may still walk 2,000 amot from the airplane door (SA 248:4; MB ad loc. 32).

footnotes: ¹¹ . See n. 3 above, which discusses the Sages’ uncertainty about whether the prohibitions of teḥumin apply to airspace more than ten tefaḥim above land. The plane in this case has flown more than twelve mil on Shabbat; therefore, according to Rambam and those who follow his position, who maintain that traveling beyond twelve mil on Shabbat is prohibited by Torah law, one who lands on Shabbat should be stringent and stay within his four amot. However, according to most poskim, traveling beyond one’s teḥum is never prohibited by Torah law, so we may be lenient cases of uncertainty. Therefore, we do not have to worry about teḥumin above ten tefaḥim. The passenger’s teḥum is established only once his plane lands, after which he has 2,000 amot in each direction, as I wrote in the main text. In any case, even according to Rambam, since the passenger’s arrival on Shabbat was unintentional, he may walk through the entire airport as long as it is enclosed by a fence (see Rema 248:4; MB ad loc. 32; Yaskil Avdi 8:20:62; Yalkut Yosef 248:4).

One whose boat docked on Shabbat may leave the boat and walk 2,000 amot in each direction. This is because until reaching the port, the boat was more than ten tefaḥim above the ocean floor, so teḥum Shabbat did not apply to it. Only once he sets foot on dry land is his teḥum established. If the port is fenced in, he may walk 2,000 amot beyond the enclosure (SA 404:1; n. 3 above).

One who traveled beyond his teḥum and then returned inside his teḥum unknowingly or due to circumstances beyond his control may still walk within his teḥum (SA 406:1). However, if he traveled beyond the teḥum knowingly, then even if he returned unknowingly, he forfeits his teḥum, though he may still walk throughout the city (SA 405:8).

Just as one may not travel beyond his teḥum on Shabbat, he also may not move his possessions outside the teḥum. If he took fruit beyond the teḥum unknowingly, even though they may not be carried more than four amot, they may be eaten. If he did so knowingly, the fruit may not be eaten (SA 405:9; MB ad loc. 52; see above, ch. 26 n. 6).

If a non-Jew brought fruit from outside the teḥum on Shabbat, as long as he brought them for himself or for another non-Jew, a Jew may eat the fruit. However, one may not carry them more than four amot. If the non-Jew brought the fruit into a home or a site that is enclosed by a fence or an eruv, one may carry the fruit within the enclosed area. In contrast, if the non-Jew brought the fruit for a Jew, that Jew and the members of his household may not eat the fruit until enough time has passed after Shabbat for the fruit to have been brought then (SA 325:8).¹²

footnotes: ¹² Two sets of laws apply to objects that arrive from outside the teḥum. The first is the standard laws of teḥum Shabbat. Objects carried outside of their teḥum are considered the same as people who left their teḥum unknowingly or due to circumstances out of their control, since objects have no will of their own. Therefore, if the objects arrived in an enclosed area, they may be carried throughout the enclosed area. However, if they were brought to a place that is not enclosed, they may be moved only four amot. If they are returned to their original place, they revert to their original status.The second set of laws relates to benefiting from prohibited actions done on Shabbat, and the intent of the person transporting the fruits determines their status. If he did so knowingly, no one may benefit from his actions, and the fruit may not be eaten. If he brought them unknowingly, then since the prohibition itself is rabbinic, they may be eaten (Pri Megadim; BHL 318:1, s.v. “ha-mevashel”; see Harḥavot 26:4:1). If a non-Jew brought the fruit from outside the teḥum for himself or for another non-Jew, a Jew may eat them; but if he brought them for a Jew, that Jew and his household may not eat the fruit until enough time has elapsed for the fruit to have been brought to them permissibly after Shabbat.The Sages established that the laws of teḥumin also apply to objects belonging to non-Jews, and such objects acquire a mekom shevita wherever they are when Shabbat began. If it was permitted to carry objects belonging to non-Jews without limit, people might mistakenly come to believe that objects belonging to Jews are also not subject to the laws of teḥum Shabbat. Ownerless items, however, are not subject to teḥumin restrictions (SA 401:1).

Teĥum Shabbat / Eruv Teĥumin

If one wants to walk on Shabbat to a place that lies beyond his teḥum, he can render it permissible by making an eruv teḥumin before Shabbat, that is, by establishing his mekom shevita at the place where he puts the eruv. By placing this eruv, he merges the old teḥum (which would not have allowed him to go where he wants) with the new teḥum (which will allow him to go there) – this is why it is called an eruv (which literally means “merging”) teḥumin. However, the distance that the eruv teḥumin affords him in one direction is lost in the opposite direction. For example, if one places the eruv teḥumin 2,000 amot to the east of his home, he may now walk 4,000 amot eastward (2,000 amot from his home to the eruv and 2,000 amot beyond the eruv), but he may no longer walk westward at all.

There are two ways to shift one’s mekom shevita. The first is by simply walking 2,000 amot in the desired direction before Shabbat begins and staying there for the onset of Shabbat. As long as one is there during the entire period of bein ha-shmashot, that becomes his place, and his teḥum Shabbat is now calculated from that point. He does not need to verbalize anything for this to take effect. It is enough for him to intend to establish his teḥum from that point. In contrast, if one is hiking in a field during bein ha-shmashot but does not intend to establish his mekom shevita there, his mekom shevita remains his home (SA 409:7; MB ad loc. 29).¹³

footnotes: ¹³ . The Sages allow a traveler who wishes to establish his mekom shevita someplace further along the way to do so by merely verbalizing this wish. This special leniency is effective as long as two conditions are met. First, it must be possible for him to reach that location before dark if he hurries. Second, at the moment when Shabbat begins, he must be within 2,000 amot of the location (SA 409:11). However, if he intends to establish his mekom shevita somewhere beyond his 2,000 amot, he loses his teḥum Shabbat, and he may not move beyond his four amot, since he cannot establish the desired location as his mekom shevita, as he is beyond its teḥum, and he cannot establish his current location as his mekom shevita either, since he pushed it out of his mind. This is the opinion of Rashba, Rosh (Eruvin 4:13), and Tur (409:11). However, according to Rambam, whenever one fails to establish his mekom shevita at his desired location, he establishes it at his current location instead. SA cites Rambam as a secondary opinion (“yesh omrim”).If one is traveling and wishes to establish his place verbally, he must specify the four amot that he intends as his mekom shevita. An example of such a verbalization might be “The four amot surrounding such-and-such tree trunk.” If he did not delineate the area precisely, according to most Rishonim the entire uncertain area is included in his mekom shevita. If he said, “My place for Shabbat is under that tree,” but half the tree is outside his 2,000 amot, he has not established a mekom shevita, and he is left with only his four amot. As mentioned in the previous paragraph, according to Rambam, whenever one does not specify his mekom shevita adequately, rendering his desired teḥum ineffective, his current location becomes his mekom shevita instead, and his teḥum is 2,000 amot from there. Under pressing circumstances, one may rely on this opinion.

The second way is to set aside two meals’ worth of food at that place and recite the declaration for making an eruv teḥumin, along with a berakha, as will be explained in the next section. An eruv teḥumin should be made only for the purpose of a mitzva – for example in order to attend a Torah lecture or a mitzva celebration. If one makes an eruv teḥumin for some other purpose, it is still effective be-di’avad (SA 415:1).

When making an eruv teḥumin, one must place it within 2,000 amot of his home. This way his home will be within the teḥum of the eruv, and he may then walk from his home to the eruv. If his home is outside the eruv’s teḥum, the eruv is ineffective, and his teḥum is measured from his home.¹⁴

footnotes: ¹⁴ At first glance, it would seem that in most large cities, setting aside an eruv teḥumin is ineffective. After all, we saw in section 4 that when one is outside the city at the start of Shabbat, we do not include the whole city in his four amot. He may travel within the city only as far as his 2,000 amot allow. If so, when one’s home is more than 2,000 amot from the eruv that one makes, the eruv is ineffective, and his status is the same as that of any other resident of the city. Indeed, this is how Beit Me’ir, Maḥatzit Ha-shekel, and Olat Shabbat understand SA 408:1, and so states Eliya Rabba 408:8 as well. According to MA and MB 408:3, 7, 10, SA agrees that one’s mekom shevita in such a case is indeed the location where he set aside the eruv. Since he was in his home when Shabbat began, he may walk within the city in the direction of the eruv, but once he has left the city, he may not return home. According to Rema, since this person’s home is in the city, if he placed an eruv outside the city, he has a connection to both places; therefore, in addition to the 2,000 amot granted him by his eruv, the whole city is considered four amot and he may walk freely within it. Even after he leaves the city, he may return to it and walk within it. BHL’s discussion of this matter concludes with an endorsement of MA’s understanding of SA (408:1, s.v. “raḥok”). However, many rule in accordance with Rema, including Baḥ, Noda Bi-Yehuda (Mahadura Tinyana 49), and AHS. SHT ad loc. 11 states that one should not object to those who are lenient in accordance with Rema. Since the laws of teḥum Shabbat are completely rabbinic, when necessary one may rely on Rema.

One can actually use an eruv teḥumin to travel 5,600 amot, not just 4,000 amot. Since the mekom shevita where he sets aside the eruv is temporary (unlike a city, as above in section 6), he may have in mind for the new teḥum created by the eruv to be oriented so that the square’s diagonal faces his desired direction. He thus gains the additional corners.

Teĥum Shabbat / Placing the Eruv Teĥumin and Reciting the Berakha

One who wishes to make an eruv by placing food must set aside two meals’ worth of food. If bread is used, it must amount to the volume of six eggs, which is approximately 300 ml. (Others maintain that it must amount to the volume of eight eggs.) If one wishes to use food that is eaten together with bread, it is sufficient to use the amount of that food that would normally be spread on or eaten together with six eggs’ volume of bread (SA 409:7). If the eruv is meant to serve several people, two meals’ worth of food must be left for each person. If a large number of people are involved and one would like to minimize the bulkiness of the eruv, he may use olive oil, chocolate spread, or peanut butter, as relatively small quantities of these foods are used with a large amount of bread. One may also use a revi’it (75 ml) of vinegar, which is enough to use as a dip or dressing for two meals’ worth of vegetables (MB 386:35; 409:36). Drinks may also be used for the eruv as long as there are two revi’iyot (150 ml) per person (SA 386:6). Salt and water may not be used for the eruv (Eruvin 26a).¹⁵

footnotes: ¹⁵ emEruvin 26a states that one may use a saltwater mixture for an eruv, and Rambam writes this as well (MT, Laws of Eruvin 1:8). However, based on the continuation of the Gemara, Tosafotad loc. s.v. “aval” state that this is limited to a case in which oil is mixed in with the saltwater. SA 386:5 presents Rambam’s opinion, and then cites Tosafot as a secondary opinion. MB ad loc. 29 states that the halakha follows the lenient first opinion.

The food must belong to the person who plans to make use of the eruv, as he uses this food to establish his mekom shevita. When the eruv is meant for several people, the food’s owner must arrange for each person to acquire some of the food, making all of them partners in it. This is accomplished by means of third person, who lifts up the food with the intent to acquire it on behalf of all those who need to use the eruv (SA 413:1).

If the food set aside for the eruv was eaten before bein ha-shmashot, the eruv is ineffective. However, after bein ha-shmashot the eruv may be eaten, because once one has established his mekom shevita during bein ha-shmashot, it remains in effect for all of Shabbat (Rema 394:2). If the eruv was left in a place where it could not be accessed during bein ha-shmashot without transgressing a Torah law (for example, if a boulder would need to be rolled away to retrieve it), the eruv is ineffective (SA 394:3; 409:3-4).

When setting aside the eruv, one should recite the following berakha: “Blessed are You, Lord our God, King of the universe, Who sanctified us with His mitzvot and commanded us regarding the mitzva of eruv” (“asher kideshanu be-mitzvotav ve-tzivanu al mitzvat eruv”). One should follow this with the declaration: “With this eruv it shall be permitted to me to walk 2,000 amot from this place in every direction.” Bedi’avad, even if he simply said: “This shall be an eruv,” it is effective. But if he said nothing at all, he has not established an eruv (SA 415:4; MB ad loc. 15).

When the eruv is meant to serve several people, their names should be explicitly mentioned as part of the declaration. One must also take care that the eruv contains two meals’ worth of food for each person who needs to rely on it (SA 415:4). If he would like the eruv to be effective for multiple Shabbatot, he should add at the end of the declaration the phrase “for all Shabbatot of the year.” Then, as long as the eruv remains in existence, it is effective (MB ad loc. 16).

An eruv may be placed by a shali’aḥ (emissary or proxy). However, a minor, a non-Jew, or one who does not believe in the mitzva of eruv cannot serve as a shali’aḥ. The shali’aḥ must recite the berakha and the declaration. If he said nothing, the eruv is not effective (SA 409:8). However, it is effective if the owner of the eruv declares: “With the eruv that my shali’aḥ is setting aside, I will be permitted to walk 2,000 amot from the eruv in every direction” (BHL s.v. “ve-yomar”).

One cannot place an eruv on behalf of another without the other person’s knowledge. One may place an eruv for his minor children, and the teḥum that it establishes is binding for them. Similarly, one may place an eruv for members of his household who are over the age of bar or bat mitzva. However, if upon hearing that there is an eruv teḥumin they object and state that they do not want it, the teḥum that it establishes is not binding for them. A child who is under the age of six is considered secondary to his mother, so an eruv that is effective for the mother is effective for her child as well (SA 414:1-2).

Teĥum Shabbat / Establishing a Conditional Eruv for All Local Residents

One may place an eruv conditionally. For example, if one knows that on Shabbat two Torah scholars will be lecturing in two nearby towns, but he has yet to decide if he will attend the lecture to the east, the one to the west, or neither, he places one eruv in the east and one in the west and stipulates in his mind that on Shabbat he will decide which teḥum to use, the one based on his home, on the eruv in the west, or on the eruv in the east. Once he has made his decision, though, he is bound by his chosen teḥum. If he did not make a conscious decision but merely started walking in accordance with only one specific teḥum, he has thus established his teḥum and may no longer change his mind and walk in accordance with a different teḥum (Eruvin 82a; SA 413:1; MB ad loc. 8).¹⁶

footnotes: ¹⁶ The Tanna’im disagree about this law. According to the Sages and R. Yehuda in the Mishna (Eruvin 36b), a stipulation is effective when placing an eruv, based on the principle of retroactive clarification (“yesh breira”). In this case, it means that when one decides which eruv he wants to use, it clarifies retroactively which of the two potential eruvin he set aside before Shabbat was the true eruv. The beraita mentions that some maintain that retroactive clarification is ineffective (Eruvin 36b and 37b). The Talmud in Beitza 38a cites the opinion of R. Oshaya that for Torah laws retroactive clarification is ineffective, while for rabbinic laws it is effective. This is the opinion of most poskim, including Rambam, Rabbeinu Tam, Rosh, Ramban, Ran, and SA YD 331:11. SA 413:1 and MB ad loc. 7 conclude similarly. Therefore, one may set aside multiple eruvin and then decide on Shabbat which eruv he will use to establish his teḥum. (Some disagree: Ri maintains that retroactive clarification is effective even for Torah laws, while Maharam of Rothenburg as quoted in Mordechai maintains that it is ineffective even for rabbinic laws.)SA 413:1 uses the expression, “It all depends on his stipulation.” This implies that if one places an eruv conditionally, such as by saying: “If the Torah scholar comes to the east, my eruv will be in the east,” and then the Torah scholar comes to the east, the person’s teḥum is set and cannot be changed.

One may volunteer to place an eruv on behalf of all residents of a locale. He then declares: “With this eruv it shall be permitted for all local residents and their guests to walk 2,000 amot from this place in every direction.” Anyone who is aware of the existence of this eruv before Shabbat, even if he did not decide that the site of the eruv is his mekom shevita, may decide on Shabbat that he wishes to walk in that direction and may rely on the communal eruv. However, one who was unaware of the eruv’s existence before Shabbat may not rely on it (SA 413:1).

If there are so many local residents that the person placing the eruv cannot leave two meals’ worth of food for each one of them, then as long as he knows that there will be no more than twenty people who will want to rely on the eruv, he may place two meals’ worth of food for twenty people and declare: “With this eruv it shall be permissible for anyone who wishes to walk 2,000 amot from this place in every direction for all Shabbatot of the year.” This allows all who are interested in relying upon his eruv to do so, on condition that they are aware of its existence before the Shabbat they rely on it (SA 413:1; BHL s.v. “le-khol eḥad”). It seems that when it is clear that someone will make use of the eruv, the berakha should be recited, but when it is uncertain whether anyone will make use of it, no berakha should be recited.

If one places an eruv unconditionally, his teḥum is determined by the location of the eruv. He may not change his mind and follow the teḥum measured from his home.