In chapter Pekudei in "33. Now they brought the Mishkan to Moses, the tent and all its furnishings its clasps, its planks, its bars, its pillars and its sockets"
we have Rashi who comments:
Now they brought the Mishkan to Moses, etc.: Because they could not erect it. Since Moses had done no work in the Mishkan, the Holy One, blessed is He, left for him the task of erecting it [the Mishkan], since no human being could erect it [by himself] because of the heaviness of the planks; and no human was strong enough to put them up, but Moses [was able to] put it up. Moses said before the Holy One, blessed is He, “How is it possible for a human being to erect it [the Mishkan]?” He [God] replied, “You work with your hand.” He [Moses] appeared to be erecting it, and it arose by itself. This is [the meaning of] what it says: “the Mishkan was set up” (Exod. 40:17). It was set up by itself. [This is found in] the midrash of Rabbi Tanchuma. -[from Midrash Tanchuma 11]"
The questions are: Why only these comments? From where were taken the thoughts for these comments? Why can't the Jewish nation do this like others people did? Ok, we know that Moshe should take part in Mishkan construction. Why couldn't he take part as a normal worker or as the leader for the construction?