Concerning the building of the third Temple, there are two opinions brought about who it will be built by. One opinion is expressed in the Zohar (1:28a) that explains that it is a “building of G-d” and will be built by G-d. Indeed, this is as well the opinion brought by Talmudic commentators:
Text 6
The future Temple that we await to be built and prepared will be redeemed and come from heaven. As expressed in the verse (Shemot 15:17) “the sanctuary, O Lord, [which] Your hands founded.”
Rashi, Talmud, Sukka 41a
On the other hand, the Jerusalem Talmud (Megilla 1:11) states that man will build the Temple. Indeed, Rambam explains that this is one of the signs of Moshiach—that he will build the Temple.
Text 7
In the future, the Messianic king will arise and renew the Davidic dynasty, restoring it to its initial sovereignty. He will build the Temple and gather the dispersed of Israel.
Rambam, Laws of Kings 11:1
The reason that Rambam is so sure about this is because the construction of the Temple is a positive commandment, as the verse (Shemot 25:8) states: “And they shall make Me a sanctuary and I will dwell in their midst.”
Being that it is a commandment, it must therefore be something that the Jewish People do—themselves—and not merely done by G-d. However, as explained in many places it is entirely possible that both man and G-d will build the Temple.
This can be done in various ways: Either man will build the entire Temple, and within it will be enclothed the Temple that will descend from Heaven, or the Temple will descend from Heaven except for the gates and doors, which will be the same as King Solomon’s temple.
It is therefore understood that there are two elements in the Temple: one that is expressive of G-d and the other that is expressive of man’s efforts.
The reason why these two elements are necessary is due to the eternal nature of the third Temple. Being that it is an everlasting edifice, it must be built by G-d—as only an eternal G-d’s actions can be eternal. On the other hand, in order that the Temple be everlasting in this world, there needs to be a certain element that man effectuates.
