נבוב לחות HOLLOW WITH TABLETS — נבוב signifies hollow, similar to, (Jeremiah 52:21) “And the thickness thereof was four fingers: it was hollow (נבוב)‎”.

נבוב לחת — The word נבוב being in the construct state and subordinate to לחות the meaning of the verse is: He made it (the altar) out of the hollow space formed by the tablets i. e. the planks of Shittim wood mentioned in v. 1 were oil all sides and the hollow space in the middle (thus the hollow space itself — which was filled with earth — formed the altar. Unlike the golden altar it had no roof; cf. Rashi on Exodus 27:8).

במראת הצבאת OF THE MIRRORS OF THE WOMEN CROWDING — The Israelitish women possessed mirrors of copper into which they used to look when they adorned themselves. Even these did they not hesitate to bring as a contribution towards the Tabernacle. Now Moses was about to reject them since they were made to pander to their vanity, but the Holy One, blessed be He, said to him, “Accept them; these are dearer to Me than all the other contributions, because through them the women reared those huge hosts in Egypt!” For when their husbands were tired through the crushing labour they used to bring them food and drink and induced them to eat. Then they would take the mirrors, and each gazed at herself in her mirror together with her husband, saying endearingly to him, “See, I am handsomer than you!” Thus they awakened their husbands’ affection and subsequently became the mothers of many children, at it is said, (Song 8:5) “I awakened thy love under the apple-tree”, (referring to the fields where the men worked). This is what it refers to when it states, מראות הצבאת “the mirrors of the women who reared the hosts (צבאות)” (Midrash Tanchuma, Pekudei 9). And it was for this reason that the laver was made of them (the mirrors) — because it served the purpose of promoting peace between man and wife viz., by giving of its waters to be drunk by a woman whose husband had shown himself jealous of her and who nevertheless had associated with another (cf. Numbers ch. V) thus affording her an opportunity to prove her innocence (cf. Sotah 15b). You may know that the מראות mentioned in the text were really mirrors (and that the word does not mean visions, or appearance, etc.), for it is said, (v. 29) “And the copper of the wave-offering was seventy talents etc. … and therewith he made [the sockets etc.]” — the laver, however, and its base are not mentioned there amongst the articles made from that copper; hence you may learn that the copper of which the laver was made was not a part of the copper of the weave-offering, which is the only copper mentioned as having been contributed by the people. Thus did R. Tanchuma 2:11:9 explain the term מראת הצבאת. And so does Onkelos also render it: במחזית נשיא, and this first word is the Targum translation of מראות, in the sense of mireors in old French, for we find that for the word (Isaiah 3:23) “And the גליונים”, which are mirrors, we have in the Targum the same word מחזיתא.

אשר צבאו [THE WOMEN] WHO CAME IN CROWDS to bring their contribution.

לעמת קלעי החצר [AND THE SCREEN…] ANSWERING TO THE HANGINGS OF THE ENCLOSURE — i. e. according to the measure of the height of the hangings of the enclosure.

אלה פקודי THESE ARE THE SUMS [OF THE TABERNCLE] — In this section are enumerated all the weights of the metals given as a contribution for the Tabernacle, of silver, gold and copper, and also there are enumerated the vessels used for every kind of service in it.

המשכן משכן OF THE TABERNACLE, EVEN OF THE TABERNACLE — The word משכן is mentioned here twice in allusion to the Temple that was taken in pledge (משכן) — as it were — (as a security for Israel’s repentance) by being twice destroyed for Israel’s iniquities (Midrash Tanchuma, Pekudei 5).

משכן העדת THE TABERNACLE OF THE TESTIMONY — The Tabernacle was a testimony to Israel that God had shown Himself indulgent to them in respect to the incident of the golden calf, for through the Temple He made His Shechinah dwell amongst them (Midrash Tanchuma, Pekudei 6).

עבדת הלוים THE SERVICE OF THE LEVITES — The things in the Tabernacle which were counted and its vessels constituted the service entrusted to the Levites in the wilderness — to carry them, to take them down and to set them up, each man according to the burden which was assigned to him, as is set forth in the section נשא (Numbers 4).

ביד איתמר BY THE HAND OF ITHAMAR — He was the officer appointed over them (the Levites) with the duty to hand over to each “house of the father” (בית אב) the service that devolved upon it.

ובצלאל בן אורי וגו׳ עשה את כל אשר צוה ה' את משה AND BEZALEEL THE SON OF URI etc. MADE ALL THAT THE LORD COMMANDED MOSES — It is not stated here: אשר צֻוָּה (Bezaleel made all that he had been commanded), but “[Bezaleel made] all that the Lord commanded Moses” — even regarding such things which his teacher (Moses) did not tell him, his own opinion was in agreement with what had been told to Moses on Sinai (Jerusalem Talmud Peah 1:1; Bereishit Rabbah 1:14). [For Moses bade Bezaleel to make the vessels first and the Tabernacle afterwards but Bezaleel said to him: “Surely, it is the way of the world (the usual way) first to build a house and then to place the household utensils in it!” He (Moses) replied to him: “So, indeed, did I hear from the mouth of the Holy One, blessed be He”. Moses further said to him: (בצלאל), you must have been sitting in the shadow of God (בצל אל), for certainly did thus God command me!” And consequently Bezaleel made the Tabernacle first and afterwards he made the vessels (cf. Berakhot 55a).

ככר [TWENTY NINE] TALENTS — A common kikkar contains sixty common manehs, and the maneh of the Sanctuary (that used for purposes connected with the Temple) was double the common maneh. Consequently the kikkar here mentioned was 120 common manehs. Now a common maneh contained 25 Sela’im (or shekels), and the kikkar of the Sanctuary equals three thousand shekels. That is why Scripture counts (mentions the number of) all the shekels that are fewer than 3,000 as a separate item, because these do not together amount to a kikkar (cf. Bekhorot 5a).

בקע (from בָּקַע to split) is the name given to a weight of half a shekel.

לשש מאות אלף וגו׳ FOR SIX HUNDRED THOUSAND [AND THREE THOUSAND etc.] — Thus were the Israelites in number, and thus did their number amount to after the Tabernacle was set up, as it is stated in the Book of Numbers (ch. II), and at this time, also, when they contributed toward the Tabernacle they were just as many (cf. Rashi on Exodus 30:16). The half-shekels of 600,000 amount to a hundred talents, each talents consisting of three thousand shekels (cf. v. 25). How is this? 600,000 half-shekels are 300,000 whole shekels, making one hundred talents and the remaining 3550 half-shekels make 1775 whole shekels, as stated in the text.

לצקת means as the Targum has it: לאתכא, TO CAST.

את אדני הקדש THE SOCKETS OF THE SANCTUARY — i. e. of the boards of the Tabernacle (the Sanctuary) which were forty-eight boards, and for these ninety-six sockets were required. The sockets for the partition vail were four in number, so we have altogether one hundred. As regards all the other sockets (those of the enclosure and of the vail at its entrance) they are not taken into account here, because “copper” was written concerning them (Scripture prescribes that they were to be of copper).

וצפה ראשיהם [HE MADE HOOKS FOR THE COLUMNS] AND OVERLAID THEIR TOPS – the tops of the columns (not of the hooks) with them (the 1775 shekels of silver), for it is said with regard of all of them (the columns of the enclosure as well as of those of the vail at the entrance) (v. 19) “and the overlaying of their chapiters and their fillets were of silver”.