Personal Grooming / Gozez (Shearing)

The melakha of Gozez (shearing) is the removal of things that grow on the body, such as hair, nails, warts, loose skin, and the like. In contrast, one who actually cuts skin and draws blood transgresses the prohibition of Ḥovel (see below 20:9.) For the Mishkan, lamb’s wool was sheared and then made into thread that was used to make the curtains. Similarly, hair was sheared from taḥash skins so that the skins would be smooth and thus fit for use as curtains in the Mishkan. We see that sometimes shearing is done in order to use material that is attached to a body, as is the case when sheep’s wool is needed to make thread, and sometimes it is done to remove something unwanted, as is the case when removing unwanted hairs to improve animal skins (Rivash; BHL 340:1 s.v. “ve-ḥayav”).

Unlike the melakha of Kotzer, where the prohibition applies only if one cuts off a plant from its life source (below 19:6), here the prohibition applies to shearing wool from the skin of a dead animal as well, because even after an animal’s death there is still a purpose to shearing its wool. Therefore, one should be careful not to pull out threads from a fur coat or a leather carpet (MB 340:5). If doing so serves a purpose, the prohibition is by Torah law; if there is no purpose, the prohibition is rabbinic.

Included in the melakha of Gozez is plucking feathers from a chicken. However, one may pluck feathers from a cooked chicken. This is because after a chicken is cooked it is considered food, and the prohibition of shearing does not apply to food (R. Eliyahu David Rabinowitz-Teomim [Aderet], Oveir Oraḥ §366; Har Tzvi, Tal Harim, Gozez 3).

Personal Grooming / Gozez and Ĥovel of Human Beings

Just as one may not shear an animal’s wool, so too one may not remove anything growing from the human body, such as hairs, nails, loose skin, and warts. One who removes them in the usual fashion transgresses a Torah prohibition, while one who removes them with a shinui transgresses a rabbinic prohibition.

Therefore, one who cuts his nails using a nail scissors or clippers transgresses a Torah prohibition, while one who pulls them off with his teeth transgresses a rabbinic prohibition (MT 9:8). One should make every effort to stop biting his nails entirely; apart from being impolite, a habitual nail biter is likely to bite his nails on Shabbat as well, thus violating Shabbat.

Similarly, one may not remove warts. If the wart is wet, cutting it with an instrument is a Torah prohibition, while removing it with a shinui, via teeth or hands, is a rabbinic transgression. If the wart is dried out and liable to fall off on its own, then even removing it with an instrument is only a rabbinic transgression (ibid.; SA 340:2; MB ad loc. 6).

One may not scrape the body to remove skin that has begun to peel. One may not even use one’s teeth to remove the skin from his chapped lips. However, one may remove dandruff, since it is only very loosely attached to the skin, and it falls out readily.

If a nail was torn off most of the way and is now painful, it may be removed using one’s hands or one’s teeth. Since most of it has already been torn off, it is viewed as if it has already fallen off, and the prohibition on finishing the job is only rabbinic. The Sages permit removing the nail with a shinui if it is causing pain (Shabbat 94b; SA 328:31; Ḥayei Adam 21:4).

One may not scratch a cut in a way that will make it bleed, because doing so constitutes Ḥovel (see below 20:9). Even though one who scratches is not interested in drawing blood, it is still rabbinically prohibited (MB 316:30). Similarly, one may not brush his teeth if it is almost certain that his gums will bleed. One also may not knowingly suck the blood out of his gums after brushing them to the point that they bleed, as this constitutes Ḥovel (MB 328:147; section 7 below).

One may remove a splinter lodged in a person’s flesh as long as one is careful not to draw blood. If the splinter is painful, one may remove it even it will certainly cause bleeding. This is because drawing blood in this situation is rabbinically prohibited, and the Sages did not extend their prohibition to cases that entail such pain (MB 328:88).

One may remove a scab from a wound that has dried and will not bleed upon the scab’s removal. This does not qualify as Gozez since scabs do not grow from the body, but rather are just dried blood from a wound (SA 328:22).

Personal Grooming / Brushing and Braiding Hair

One may not brush or comb one’s hair on Shabbat, because when doing so hairs are pulled out. This is actually a beneficial phenomenon. Every day a person sheds dozens of hairs naturally. People would rather that hairs with weak roots be pulled out during brushing rather than fall out on their own in the course of the day, thus making their hair unkempt and their clothes unsightly. In any event, since one may not brush his hair on Shabbat, brushes are considered muktzeh and may not be moved on Shabbat (SA 303:27).

Nevertheless, one who wishes to make one’s hair neater may use a special brush with soft or widely spaced bristles, so that there is a reasonable chance that it will not pull out hair. Then, even if he does happen to pull out hair, he does not violate a melakha. This is because his intention is not to pull out hair, hair will not necessarily be pulled out, and the brush is not muktzeh. In order to make sure it does not look like he is using a prohibited brush, it is advisable to designate a brush for use specifically on Shabbat (see SSK 14:50).¹

footnotes: ¹ One commits Gozez whether shearing because he wants the wool or because he wants to beautify the body by removing unsightly growth from it. The latter is similar to shearing the taḥash skins in order to make them into curtains for the Mishkan. Since it is generally in one’s interest for some hairs to fall out while he is brushing his hair, doing so is prohibited by Torah law (Rivash §39; SHT 303:72). However, according to MT, Laws of Nazirism 5:14, a nazirite who brushes his hair is not subject to lashes. Radbaz explains that even though it is in the interest of the nazirite for some hairs to fall out, the prohibition is only rabbinic because the hairs have weak roots and thus are likely to fall out in any case. Eglei TalGozez 15 suggests this as well. Kesef Mishneh explains that according to Rambam the prohibition is rabbinic because one does not intend for his hair to fall out; he is primarily concerned with arranging his hair, not pulling it out. Additionally, it is not certain that any hair will be pulled out at all.

One may gently rub one’s hair or beard, and one may use one’s fingers to arrange them and to remove anything stuck in them, as long as one is careful not to pull out hairs. Even if these actions might cause hairs to be removed, one may do so, as this is unintentional. One who generally tugs at his beard in a way that causes hair to be pulled out must refrain from doing so on Shabbat.

The Sages forbade braiding hair on Shabbat, because making a braid resembles the melakha of Boneh. Similarly, one may not undo a braid, because this resembles melakha of Soter. One may gather hair into a ponytail, as this does not create a structure. Similarly, one may part one’s hair using one’s hands, but one may not use a brush or comb to do so, as this will pull out hairs (SA 303:26; MB ad loc. 84).

Braiding a wig is also forbidden because it resembles weaving – the melakha of Oreg – while one may not undo a braid because this constitutes “undoing a weave” – the melakha of Potze’a (MB 303:82; SHT ad loc. 71). It is proper to refrain from combing a wig, but one may do so using a soft brush that will not pull out hairs (SSK 14:52). If a wig has become so tangled that it cannot be worn outside, then one may not style it even using one’s hands, as it constitutes Makeh Be-fatish (Ketzot Ha-shulḥan 143, Badei Ha-shulḥan 6).

It is rabbinically prohibited to curl one’s hair, which includes men curling their sidelocks (peyot), because this is similar to Boneh. Straightening hair or sidelocks is prohibited because of Soter. But if the sidelocks were already curled, they may be twirled even though this may tighten the curls, because no new structure is formed (Tiferet Yisrael on Shabbat ch. 10, Yakhin 35; see Ketzot Ha-shulḥan 146, Badei Ha-shulḥan 21).

One may not use hair spray or oil to keep one’s hair in place, because this is similar to Boneh (Rivash as cited in BHL 303:27 s.v. “laḥof”). One may not use these substances on wigs either (SSK 14:56). However, women may spray perfume on their hair or bodies (MB 128:23; SSK 14:56-57).

Personal Grooming / Applying Makeup

One of the 39 melakhot forbidden on Shabbat is Tzove’a (dyeing). By Torah law, it is limited to long-lasting paints or dyes applied to surfaces that will retain them for an extended period (see below 18:5). The Sages, however, prohibited even color that will not last for a long period, and even if it is applied to a surface that will not retain the color. One example of this is the prohibition on the use of makeup, which colors one’s skin for a short time. Accordingly, one may not use eye shadow, blush, lipstick, or clear lip gloss that provides a shine. Similarly, one may not use even clear nail polish, because the shine it provides is considered color. While this prohibition pertains to applying makeup, removing makeup with water or cotton is permissible. Cotton balls soaked in water should not be used, because of the prohibition of Seḥita.

It is also forbidden to apply foundation, a cosmetic used to even out one’s complexion. This prohibition is more severe than the prohibition on using other types of makeup, because in addition to transgressing the rabbinic prohibition of Tzove’a, one might also transgress the Torah prohibition of Memare’aḥ (see the next section) if one is using cream foundation.

One may use powder, however, whether white or colored, because powder has no adhesive agent. It is only when the material used for coloring adheres to the skin that there is a prohibition of Tzove’a; in contrast, if it just stays on the surface of the face and does not adhere to it, one may apply it (Igrot Moshe OḤ 1:114; Yeḥaveh Da’at 4:28). Some are stringent even in such cases (Maharam Brisk 1:23; Beit Yisrael §56). However, since this disagreement pertains to a rabbinic prohibition, the halakha is in accordance with those who are lenient.

The prohibition on wearing makeup is one of the most difficult to follow. For a woman who is used to putting on makeup every day, it is not easy to refrain from doing so on Shabbat, especially since it is precisely Shabbat when everyone tries to look their best. However, if we explore the issue more deeply, perhaps we can suggest that this, on the contrary, relates to the main idea of Shabbat, a day of holiness and rest. Shabbat is when we take a break from the tension that we experience throughout the week. We work so hard to present ourselves to others as more beautiful than we naturally are, in an attempt to meet society’s cruel and superficial standards of beauty. In contrast, Shabbat helps us truly relax by strengthening our faith and belief in divine providence. We can achieve this spiritual relaxation when we attain an internal acceptance of existence as it is, and an appreciation of our natural beauty, which we highlight with clothing and jewelry. This is oneg Shabbat.

Nevertheless, before Shabbat, one may, and even should, put on makeup. The Sages state: “One who labors before Shabbat will eat on Shabbat” (AZ 3a). During the week, it is our mission to fix the world, improve it, and prepare it for Shabbat. This allows us to absorb the divine light more completely. However, if we are unable to prepare ourselves fully for Shabbat – for example, we know that makeup applied on Friday will not last through the whole of Shabbat – once Shabbat arrives we must calmly and joyfully accept existence as it is. This very acceptance is what will allow us to continue to fix and improve the world during the week.

Personal Grooming / Applying Oils, Perfumes, Creams, and Lotions

One may apply oil to the hands or body on Shabbat in the manner that people normally anoint themselves for pleasure. Similarly, a woman may rub her hair or body with perfumed oil. It is true that the Sages forbade perfuming a garment, because scenting clothing involves Molid (producing something new that did not previously exist), which is similar to performing a melakha (Beitza 23a; Beit Yosef and Rema 511:4). However, there is no prohibition on applying perfume to the body or hair, because the scent is completely secondary to the body, and therefore it is not considered producing something new.²

footnotes: ² . Some forbid making the body smell good, on account of Molid (Taz 511:8; MA 511:11; Ben Ish Ḥai, Year 2, Tetzaveh 11). At the opposite extreme, some maintain that one may infuse a garment with scent (Rishon Le-Tziyon, based on Rif, Rambam, and Rosh). However, most poskim maintain that while one may not make clothing smell good, one may make the body smell good (MB 128:23; Yeḥaveh Da’at 1:31; SSK 14:36).

Although one may rub his body with oil, he may not apply cream because of the prohibition of Memare’aḥ, which is a tolada of Memaḥek (see below 18:6). Memaḥek refers to smoothing rough surfaces such as leather or wood, while Memare’aḥ involves evenly applying a substance to an object in order to make it smooth.

Therefore, one may not apply any type of cream or ointment to the skin, because in doing so one smoothes the cream onto the skin. Some object that this should not be prohibited, since the cream is meant to be absorbed by the body rather than to remain on the surface of the skin. However, this is incorrect, since even when one wants the cream to be absorbed, he also wants some of it to remain on the skin’s surface to make it smooth. Hence the prohibition of Memare’aḥ applies. In contrast, if the cream is watery, such that if it is left on a surface it will spread out, there is no prohibition of Memare’aḥ, and one may apply it to the body.³

footnotes: ³ If one would like all the cream to be absorbed into the body and none to remain on the skin, then there is no prohibition of Memare’aḥ (MA 316:24; MB ad loc. 49). Therefore, if one is sick enough that he may receive medical treatment on Shabbat, and he requires a cream, it may be spread on the skin and rubbed in until it is absorbed entirely by the body (Da’at Torah 328:26; R. Shlomo Zalman Auerbach cited in SSK ch. 33 n. 64). However, those who use cosmetic cream for pleasure or beauty do not want it to be entirely absorbed. Rather, they want some to stay on the surface of the skin, making it smooth and beautiful. Therefore, it is prohibited by Torah law to apply that cream.

Liquid insect repellent may be used on Shabbat, but if it is a solid, one may not spread it on the body because of the prohibition of Memare’aḥ.

One who is experiencing mild discomfort may not apply medicinal oil. Furthermore, a healthy person may not apply medicinal oil for pleasure, since the Sages prohibited the use of medicines on Shabbat. However, if one is truly suffering, he may use medicinal oil. If this oil is also used by healthy people, then since it will not be apparent that it is being used medicinally, even one who is experiencing discomfort may apply it (SA 327:1; below 28:4-5). The laws pertaining to massage, both professional and amateur, will be explained below (28:13).

Personal Grooming / Bar Soap, Liquid Soap, and Wipes

While one may use liquid soap to wash one’s hands, the general practice is to be stringent about bar soap or thick liquid soap. There are two reasons for this. First, using bar soap or thick liquid soap resembles Memaḥek, since using a bar of soap smooths its surface and thick liquid soap is spread on the hands or body. Second, when one uses these kinds of soap it looks like he is producing something new, since the soap changes from solid to liquid. Although according to many poskim this use is not technically prohibited, because the person using the soap does not intend to smooth it and because the small amount of soap that is used is dissolved in the water, so it does not seem like anything new is being created, nevertheless, since there is some resemblance to Memare’aḥ and Molid, the common custom is to be stringent and avoid using bar soap or thick liquid soap. Those who are lenient have an opinion to rely upon.

If a thick liquid soap spreads out upon being left on a surface, it is considered liquid, and all would agree that one may use it on Shabbat. If it is uncertain whether a substance is considered thick or liquid, one may be lenient.⁴

footnotes: ⁴ . MB 326:30 is stringent, based on Tiferet Yisrael, and maintains that one should not use this kind of soap because of Memare’aḥ. This is also the opinion of Ma’aseh Ish, p. 109, and R. Shmuel Laniado, Shulḥan Ha-melekh. Ben Ish Ḥai Year 2, Yitro 15 is stringent on account of Molid. However, several poskim are lenient, including Paḥad Yitzḥak, Ginat Veradim, and Pe’ulat Tzadik. Ketzot Ha-shulḥan agrees (138, Badei Ha-shulḥan 31). Yabi’a Omer 4:27 elaborates on this approach, adding that Rambam presents it in a responsum. R. Shlomo Zalman Auerbach, cited in SSK ch. 14 n. 49, states that technically one may use this kind of soap. Rather, it is an example of “things that are permitted but custom forbids,” and in such cases one should follow the custom. In practice, both SSK 14:18 and Or Le-Tziyon 2:35:5 forbid using it. R. Ovadia Yosef writes in Halikhot Olam vol. 4, p. 108, that it is proper to be stringent, and that this is the custom. However, it would seem that under pressing circumstances one may rely on those who are lenient, and even more so if one is uncertain whether his soap is considered thick or liquid. If there are cracks in bar soap and one wishes to smooth them out, this is prohibited according to all opinions.

One may use wet wipes to clean a baby, to clean one’s body in general, or to clean a table and the like. Some are stringent because they maintain that there is a problem of Seḥita, since when using a wipe, one presses on it and squeezes out some moisture, which would help in cleaning. Nevertheless, the lenient opinion is the primary one, because the purpose of a wipe is to use the moisture on the surface of the wipe to clean more effectively. The purpose is not to squeeze out the moisture inside the wipe in order to wet the dirty area. If that were one’s goal, he would simply wash the area with water. As long as the wipe remains damp, he has no interest in the moisture that has not been squeezed out and separated from it, and thus no transgression has taken place. Even if, by chance, a couple of drops were squeezed out, since one did not intend for this to happen, he has not transgressed.⁵

footnotes: ⁵ Those who are stringent include Orḥot Shabbat 13:46 and Ḥut Shani vol. 2, p. 209. Minḥat Yitzḥak 10:25 and Shevet Ha-Levi 8:59 and 10:58 incline this way as well. Opposing them are Har Tzvi 1:190 and Va-ya’an Yosef OḤ §163, which rule leniently. Many others have also permitted this, including Igrot Moshe OḤ 2:70; SSK 14:37 and n. 99 based on R. Shlomo Zalman Auerbach; Rivevot Ephraim 6:194:3; Menuḥat Ahava vol. 2 ch. 12 n. 20; and Be-mar’eh Ha-bazak 3:48. See Harḥavot.

As we have seen (above 13:11), if one went to the bathroom and has no way to wipe himself other than to tear toilet paper, he may do so with a shinui such as using his elbows to pull the paper from the roll. This is because the Sages permitted transgressing a rabbinic prohibition to avoid great embarrassment. One may also, when necessary, wet toilet paper so it will clean more effectively, as long as one does not intend to squeeze out water from the toilet paper but only to make use of the moisture.

Personal Grooming / Brushing Teeth and Toothpaste

One may brush one’s teeth on Shabbat to clean them and to treat bad breath. Similarly, mouthwash may be used to freshen one’s breath. However, it is proper to refrain from using toothpaste, the same way we refrain from using bar soap or thick liquid soap. While it is true that some forbid brushing teeth on Shabbat, either due to the concern of Seḥita, because the gums might bleed, or because the bristles of the toothbrush might break, nevertheless, the primary halakhic position is that one may brush one’s teeth with a toothbrush le-khatḥila. It is only in a case where it is almost certain that the gums will bleed that this is prohibited.⁶

footnotes: ⁶ Those who prohibit include Minḥat Yitzḥak 3:48 and Orḥot Shabbat 17:29. SSK states in 14:39 that the custom is to be stringent. The logic of those who forbid brushing is that it causes bleeding and can break the bristles of the toothbrush. Both claims are incorrect. Since it is rare for either thing to happen, they would be cases of davar she-eino mitkaven and thus brushing is permitted. Some also raise the problem of Seḥita, as water may be squeezed out of the bristles during the brushing. In response, those who permit explain that such squeezing is a psik reisha de-lo niḥa lei in a case of a double rabbinic prohibition. First, wringing out hair and the like is only rabbinically prohibited; second, it is done in a backhanded way. R. Shlomo Zalman Auerbach maintains that it is to one’s advantage (niḥa lei) for the water to be squeezed out, because this improves the cleaning. However, generally the bristles of a toothbrush are neither very long nor very tightly packed, so usually no Seḥita occurs at all. If one rinses his mouth with mouthwash before brushing, then R. Shlomo Zalman Auerbach would agree that it is a psik reisha de-lo niḥa lei. Those who permit tooth brushing in practice are Seridei Esh 2:28; Igrot Moshe, OḤ 1:112; Or Le-Tziyon 2:35:6; and R. Shlomo Zalman Auerbach (Shulḥan Shlomo 320:28:2). Ketzot Ha-shulḥan and Yabi’a Omer 4:27-30 permit using toothpaste as well.

One may wash off the toothbrush with water after brushing, as one normally does, even if one does not intend to use the toothbrush again on Shabbat. This is not considered preparing for the weekday on Shabbat, because it is simply a matter of routine and is not considered a significant chore. Furthermore, removing the residue from the brush also serves a purpose on Shabbat, as leaving it dirty would be disgusting (see MB 667:6; below 22:16).

One may clean one’s teeth with a toothpick (SA 322:4). If there is no toothpick available, a match may be used. While it is true that matches are muktzeh, they are kelim she-melakhtam le-isur, and one may handle them in order to use them for a permitted activity (below, 23:7). Of course, one must remember that one may not sharpen the match for this purpose, as sharpening it would violate a Torah prohibition.

One may use denture adhesive powder to attach false teeth to the gums, as this is meant for the short term (Har Tzvi; Tzitz Eliezer 15:25; Yalkut Yosef 314:17; as opposed to SSK 14:40, who is stringent).

Personal Grooming / Bathing on Shabbat

The Sages forbade bathing the body in hot water on Shabbat. This is because some people were so eager to bathe in hot water that they would heat the water on Shabbat, thus transgressing both Hav’ara and Bishul. When they were admonished, they would claim that the water had been heated before Shabbat. Therefore, the Sages forbade bathing one’s body on Shabbat, even in water heated before Shabbat. However, one may wash less than half of the body in hot water. As long as one refrains from washing most of the body, there is no concern that one will succumb and heat the water on Shabbat for the lessened pleasure of bathing less than half of the body. Even when washing each limb individually, one still may not wash the majority of one’s body with hot water (Shabbat 40a; SA 326:1).

We have seen that one may use hot water already available in the boiler as long as this usage does not cause additional water to be cooked (above 10:24). We have also seen that many permit using water that was heated on Shabbat with solar power (10:25). According to this approach, one may use this water to wash the hands, face, and less than half of the body. However, one still may not use this water to wash most of the body on account of the rabbinic enactment.

The prohibition on washing the body is specifically limited to hot water. One may wash the whole body in cold or lukewarm water whose temperature is lower than body temperature. One may even turn on the hot water tap so that the water will not be cold, as long as this does not cause the cold water entering the boiler to be cooked (as explained above 10:24-25).

It is also important to note that the prohibition of washing the body in hot water is limited to normal circumstances. One who suffers greatly if he must go a whole day without bathing in hot water may wash his whole body in water that was heated on Friday or by a solar boiler (R. Akiva Eger; BHL 326:1).

One who bathes on Shabbat must take care not to wring out his hair with his hands while washing or drying off, in order to avoid the prohibition of Seḥita. He may, however, towel his hair dry. Since he is not interested in the water that is wrung from the hair and absorbed by the towel, there is no prohibition. A woman who always combs or brushes her hair after bathing must be careful not to wash her hair on Shabbat, in order to avoid the prohibition of Gozez (see section 3 above).

The Sages further cautioned that if one washes in a river, spring, or sea in an area where there is no eruv, he should shake the water off himself when he gets out and thus avoid carrying the water the distance of four amot. He does not have to be totally dry; it is sufficient to remove the excess water that drips from his body. In contrast, there is no rabbinic decree against walking in reshut ha-rabim when wet from rain. This is because rain does not get one as wet as bathing, and even if there is enough rainwater on one’s body that it could be considered carrying, the Sages were not stringent, since the rain falls on him against his will (Shabbat 141a; Beit Yosef and SA 326:7; Taz ad loc. 2).

Personal Grooming / Swimming and Immersion in a Mikveh

The Sages prohibited swimming on Shabbat, because one might come to build or mend a raft. One who lifts his feet from the ground and floats in the water is considered swimming. However, if he does not lift his feet, then he is considered bathing, which is permitted (Beitza 36b; Shabbat 40b; SA 339:2). Technically, one may swim in a pool located in a fenced-off area and where the water is confined by the walls of the pool, as in such a case we are not concerned that one might build a raft or carry water outside the eruv. Nevertheless, since nowadays swimming has become one of the most common weekday leisure activities, it is prohibited as a weekday activity (uvdin de-ḥol). Furthermore, there is a concern that after swimming, people will wring out their bathing suits. Moreover, it is improper for one to waste free time on Shabbat with leisure activities instead of dedicating it to Torah study.⁷

footnotes: ⁷ . Even though technically one may wash one’s whole body in cold water, the Ashkenazic custom is to be stringent out of concern that one might wring out his hair upon leaving the water, that one might carry water four amot in a reshut ha-rabim, or that one might come to swim (Terumat Ha-deshen §255; Maharil Ḥadashot §139; MA 326:8; MB ad loc. 21). However, even those who are stringent regarding Shabbat agree that on Yom Tov one may bathe the entire body in cool or cold water. One who does so must be careful not to wring out his hair with his hands. He must dry off with a towel instead (SSK 14:11). Some write that even when using a towel, one must be careful to be gentle in drying off (Ben Ish Ḥai, Year 2, Pekudei 8). I did not include the Ashkenazic custom prohibiting bathing in cold water in the main text, because it rarely arises, and it applies only to those few individuals who normally bathe for pleasure in cold water. In contrast, if there is an element of anguish involved, we are lenient about washing in either cold or hot water. Nevertheless, it is clear that Ashkenazic custom forbids swimming in a pool. While it is true that Sephardic custom follows the letter of the law and permits both bathing in cold water and swimming in an enclosed pool in a reshut ha-yaḥid, nevertheless, it seems that swimming in a pool should be prohibited even for Sephardim. This is because people generally swim in swimsuits, and there is a serious concern that they might wring them out. Furthermore, in the past the entire leniency of swimming in a pool was relevant only to uncommon cases of individuals who had a small pool in their yard and would float around in it for a short while. In contrast, pools built today are meant to be used for extended periods. Because swimming in a pool is a normal leisure activity, it is considered a weekday activity. If swimming on Shabbat were permitted, people would waste time that they could use for Torah learning, and they would miss out on that key aspect of Shabbat. Yalkut Yosef 326:11 (in vol. 4, p. 69) states similarly. See also the laws regarding running and exercising, below 22:7-8.

One may immerse in a mikveh on Shabbat to remove impurity. Even though the Sages prohibit immersing implements (tevilat kelim) on Shabbat, this is because it resembles fixing the implement, since as a result of the immersion the implement may be used. A person, however, may immerse on Shabbat to purify himself since he may anyway bathe in cold water and thus it does not resemble an act of fixing or improving something (Beitza 18a; SA 326:8). While it is true that, for several reasons, the Ashkenazic custom is to avoid bathing in cold water on Shabbat, when it is done for the purpose of a mitzva, the custom is not to be stringent (Rema, YD 197:2). Therefore, men who are accustomed to immerse as an act of piety may do so on Shabbat as well.

The poskim disagree whether the rabbinic ban on bathing on Shabbat applies to immersion in a mikveh. Some maintain that the Sages did not include immersion for the sake of a mitzva in their decree, and thus one may immerse in hot water as long as it was heated in a permissible fashion (Korban Netanel). Others maintain that the enactment applies to this immersion as well, and thus one may not even immerse in hot water on Shabbat (Noda Bi-Yehuda). Many are customarily lenient and immerse in hot water. Those who wish to be stringent should make sure that the water is lukewarm, lower than body temperature, as most poskim agree that one may bathe on Shabbat. Thus, one may certainly immerse for the sake of a mitzva.⁸

footnotes: ⁸ Terumat Ha-deshen §255 rules that according to the Ashkenazic custom, which does not allow bathing in cold water, a woman who could have immersed before Shabbat may not immerse on Shabbat. Accordingly, the Vilna Gaon writes that a man who had a nocturnal emission may not immerse on Shabbat. Nevertheless, the overwhelming majority of Ashkenazic poskim permit any immersion on Shabbat. Rema YD 197:2, AHS ad loc. 8, and Taharat Yisrael 14 rule accordingly with regard to women’s immersion. Those who permit men’s immersion include Olat Shabbat 326:15; Eliya Rabba ad loc. 5; Tosefet Shabbat 12; and Igrot Moshe OḤ 4:74.The Sages did not prohibit immersion in hot water on Shabbat, according to Korban Netanel, Shabbat 2:100 and Ḥesed Le-Avraham §30 (as cited in SHT 326:5). Many Aḥaronim attest to the practice of women immersing on Friday night in hot water (Divrei Ḥayim 2:26; R. Yehuda Ayash in Responsa Bnei Yehuda 2:32; Responsa Divrei Yosef §64). In contrast, others maintain that immersion in hot water is included in the rabbinic prohibition (Noda Bi-Yehuda, 2: 24; Ḥakham Tzvi §11; Beit Meir, beginning of §326; Ḥayei Adam 70:1; and R. Akiva Eger 1:17). SHT 326:5 states that one may be lenient only under pressing circumstance. However, in practice many are lenient and permit women to immerse in hot water. Thus state Orḥot Shabbat 2:21, n. 30; Menuḥat Ahava 2:10, n. 173; and Badei Ha-shulḥan 197:17. Livyat Ḥen §79 states (following Ḥakham Tzvi) that le-khatḥila a woman should immerse during bein ha-shmashot (dusk), since rabbinic prohibitions on Shabbat do not apply to mitzvot that are undertaken during bein ha-shmashot. If she is unable to immerse during bein ha-shmashot, she may immerse in hot water on Shabbat. It seems to me that those who wish to be stringent should preferably immerse in lukewarm water, since there are three opinions regarding the nature of the prohibition of washing in hot water (mentioned in the previous section):1) According to Beit Me’ir and R. Akiva Eger, even water that has been heated slightly to remove its chill is prohibited.2) According to Ḥakham Tzvi §11, Ḥatam Sofer OḤ §146, and Tehila Le-David 326:3, the prohibition applies to lukewarm water, but water that has been heated merely to remove its chill is permitted.3) According to Noda Bi-Yehuda 2:24, Ḥayei Adam 70:1, Zera Emet 1:71, and AHS 326:3, the prohibition pertains only to hot water, but lukewarm water is permitted.Thus, even according to the opinion that one may not immerse in hot water, according to Noda Bi-Yehuda and those who follow his approach one may immerse in lukewarm water. If the heat of the water is slightly cooler than body temperature, it may be that Ḥakham Tzvi and those who follow his approach would agree that this is not forbidden. Therefore, one who wishes to be stringent should heat the water to body temperature or lower. The subsequent immersion thereby complies with the overwhelming majority of poskim, and at the same time does not cause suffering.