It is inaccurate to describe mitzvot as being “incumbent upon every Jew.” Some mitzvot are only for Kohanim, some are for Levites, some are only for farmers, a few are just for women, etc., etc. It is impossible for any one Jew to do all 613 mitzvot. As Hillary wisely said, it takes a village.
But beyond that, there are mitzvot that are not incumbent upon anyone at all. The first mitzvah of our parsha is an example of this rare kind of mitzvah.
G-d spoke to Moshe, saying: “Speak to the Israelites and they shall take for me a portion (terumah). Take my portion from everyone whose heart compels him to give. This is the portion that they shall take from them: Gold, silver, copper, sky-blue [wool], purple [wool]…
They shall make Me a sanctuary and I will dwell among them.
Shemot 25:1-4,8
In the words of the Brisker Rov (Rabbi Yitzchak Zev Soloveitchik, 1886-1959):
The communal collection on behalf of the Mishkan was a mitzvah and an obligation, as the verse states, “Speak to the Jews and they shall take for me a portion…” This is the language of a command and a positive mitzvah. However, the essential quality of this mitzvah is that it is communal obligation and not an individual obligation. It is just like the mitzvah of building the Mishkan – the obligation [to build] is on the community and not the individual, as is made clear by Maimonides in his Sefer HaMitzvot.
The question runs deeper. The Talmud teaches that following orders is greater than volunteering (Kiddushin 31a). This surprising perspective is based on the idea that the more difficult the task, the more meaningful and rewarding the outcome. Volunteering is special, but it is a natural tendency in good people. More extraordinary is following orders – because orders turn people off. Overcoming that mental obstacle and doing the deed without the help of the natural excitement and drive that comes with being a volunteer makes for an even greater act. This is the advantage of mandatory mitzvot (cf. Tosefot Tuch, ad loc.).
In light of this concept, our question is strengthened. Why is the mitzvah of our parsha different? Why were the Jews deprived of a mitzvah-command to participate in the construction of the Mishkan?
The answer is that G-d wants the Mishkan built by people who go beyond the call of duty. The compelling words of Rabbi Moshe Chaim Luzzatto (1707-1746) can help us understand why.
One who truly loves the Creator will not consciously limit their observance to the well-known obligations incumbent upon every Jew. Rather, what happens to him is what happens to a boy who loves his father. If his father just hints that he likes something, the son will strive to do the thing as much as he can. Even if his father said it only once and in a half-sentence, that’s sufficient for the son to understand his father’s preferences… he doesn’t need an explicit command or to be told again. We see this happening all the time between lovers and friends, husbands and wives, and fathers and sons…
Don’t say, “I wasn’t commanded [to do] more, it’s enough for me to do what I’ve been told.”
The Path of the Just, chap. 18