And let them make Me a sanctuary that I may dwell among them.
It was called a Sanctuary (literally “a place of holiness”) because it was the dwelling place of the Holy Name.
Tell the Israelite people to bring Me gifts; you shall accept gifts for Me from every person whose heart so moves them.
Terumah is something set apart; the meaning is: let them set apart from their possessions a voluntary gift in My honor.
Midrash Tanchuma, Terumah 2:1
R. Simeon the son of Lakish explained this verse as follows: Once there were two merchants who were traveling together. One of them held a bolt of silk material in his hand, while the other held some pepper. They said to each other: “Let us exchange our merchandise.” One took the pepper and the other took the silk. What one of them had previously owned was no longer his, and that which the other had owned was, likewise, no longer his. With the law, however, this is not so. If one many studies Tractate Ze’raim, and another Tractate Mo’ed, and they instruct each other, each possesses knowledge of both. Truly, is there any merchandise more valuable that this?
Rabbi Adin Steinsaltz
it does not say “in it” but “in their midst”. (Alshekh) … Its sanctity is not due to its structure or to the materials from which it is built, but to the fact that the Jewish people resides around it.
In essence, this is true of every sacred object. Every holy vessel presents an opportunity to establish a holy connection, but this does not happen automatically; the sanctity exists only when the object is used. … they only receive their inner essence when combined with one’s performance of the mitzvot associated with them. … Therefore, while it is certainly important to deal with the construction of the physical Tabernacle, it is particularly critical to deal with its inner aspect as well: the human tabernacle.
…the Tabernacle was based precisely on the totality of what the people have inside them, on each person’s generosity and capacity for giving: the small and the great, the rich and the generous. From the combination of all of them, from top to bottom, a sanctuary is made, and in the entirety of what is built, God’s glory resides.
Rabbi Yehudah Leib
Thus they said: “This is my God and I will enshrine Him” (Shemot 15:2), meaning that I will make [myself into] a shrine for Him. The children of Israel themselves were a foundation for “Your dwelling”! But after the sin [of the Golden Calf]: “Let them make Me a sanctuary” (Shemot 25:8), and [only] through it “I will dwell in their midst.”
…on the holy Sabbath there is a revelation of holiness like that before the sin, and there is no need for the “reduction” of a sanctuary.
Thus it was surely not for naught that God said: “Let them bring Me gifts.” They were filled with longing to return to their prior rung, that which they had attained as they received the Torah. But because of the sin, they just weren’t able to reach it. Then God was compassionate with them and gave them the idea of the mishkan and its vessels.
…each one of Israel has a particular portion within Torah, yet it is also Torah that joins all our souls together.
[there is a parable] of two merchants, one who has silk and the other peppers. Once they exchange their goods, each is again deprived of that which the other has. But if there are two scholars, one who has mastered the Order of Seeds, and the other who knows the Order of Festivals, once they teach each other, each has both orders.
The same was true in building of the tabernacle. Each one gave his own offering, but they were all joined together by the tabernacle, until they became one. Only then did they merit Shekhinah’s presence.