Exodus 25:3

And this is the separation which you shall take of them: gold, and silver, and brass;

V’ZOTH’ (AND THIS) IS THE OFFERING. By way of the Truth, [the mystic lore of the Cabala], this is like the expression, And the Eternal gave Solomon wisdom. Cabalists saw an allusion to the Divine Glory. It is also written: ‘v’zoth’ (and this) is it that their father spoke unto them and blessed them; ‘v’zoth’ (and this) is the blessing; the Eternal’s doing is ‘zoth’ (this). The Rabbis have already alluded to this in Bereshith Rabbah on the basis of the verse, I understand from the elders. The discerning student will understand.
And in Eileh Shemoth Rabbah the Rabbis have said: “And this is the offering which ye shall take of them — this refers to the congregation of Israel, which is the heave-offering, as it is said, Israel is the Eternal’s hallowed portion, His first-fruits of the increase.” And it is also said there: “The Holy One, blessed be He, said to Israel: I have sold you My Torah; and I, as it were, was sold with it, for it is said, ‘v’yikchu li terumah’” [which the Midrash takes to mean: “and they shall acquire Me as an offering”]. For the offering shall be Mine, and I am with it, similar to: My beloved is mine, and I am his. Similarly, He said, according to all that I show thee, for it is I who show [the pattern of the Tabernacle, and the pattern of all its vessels]. The statement, it hath been shown to thee,, 27:8. also alludes to the word “I”; similarly, which is being shown to thee. And so did David say, All this [do I give thee] in writing, as the Eternal hath made me wise by His hand upon me, for the hand of G-d was upon David [to show him the pattern of the Sanctuary and of all its works].

וזאת התרומה, the word זאת means that no substitutes for the materials listed would be acceptable, such as perishables, for instance. Even the kind of gemstones (pearls, for instance) not usable for Aaron’s breastplate, were not accepted. The only type of contributions that were accepted were those that in themselves would be usable in the construction of the Tabernacle and its paraphernalia.

'וזאת התרומה וגו, “and this is what the contribution is to consist of, etc.;” thirteen different categories of contributions are listed here. The prophet Ezekiel in Ezekiel 16,10, lists the thirteen garments (including jewelry) in which the Lord is going to dress the Jewish people in the future which correspond to this. (Tanchuma, section 5 on our portion)

וזהב וכסף ונחושת, “as well as gold, silver, and copper.” These three elements correspond to the gifts (tzedakah) a person dispenses; when he does so while in perfect health, it is compared to gold, i.e. as if he had handed out gold. If he dispenses charitable gifts while sick, this is accounted for him as if he had given away silver. If he bequeaths money to charity to be dispensed after he has died, it is considered as if he had handed out copper coins. An alternate interpretation: the word “gold,” is a reference to the Kingdom of Babylon concerning which we read in Daniel 2,38: אנתה הוא ראשה די דהב, “you are the head of gold.” [Daniel speaking to Nebuchadnezzar, King of Babylon. Ed.] The word: “silver,” is an allusion to the Kingdom of Persia, and the ten thousand talents of silver Haman offered the King in order to be allowed to destroy the Jews [and compensate him for lost tax revenue. Ed.] (Esther 3,) Copper, which is the cheapest of all the metals, is an allusion to the Kingdom of the Greeks, which was the weakest of the three empires mentioned. This is followed, by the skins of the various animals forming the upper layers of the Tabernacle’s roof, which are an allusion to the empire of the Romans, considered inferior by our author. Finally, שמן, ”oil,” is an allusion to the Messiah, of whom we read in Psalms 132,17: ערכתי נר למשיחי, “I have prepared a lamp for My anointed one.” (Compare Sh’mot Rabbah 35,5 as well as Tanchuma, section 7 on our portion).