pikudei

אלה פקודי המשכן משכן העדת
These are the accountings of the mishkan,the mishkan of the testimony.
Rashi says that it says mishkan twice to allude to the fact that the bais hamikdash would be taken from us as a משכון-collateral - two times because of our sins. The Maharal asks why would the Torah tell us this now when we're just summarizing what went into the mishkan, & not before when we talked about the building of the mishkan?
He answers that here the Torah is also alluding to what made it possible for it to be destroyed; the fact that Moshe counted everything that was given, gave the mishkan an עין הרע, which in turn enabled it to be destroyed. The same way the first luchos were destroyed because they were given in a grandiose manner that gave them an עין הרע, here too, by counting, he gave the mishkan an עין הרע.
Why would Moshe count it when he knew what could happen?
The Medrash Tanchuma says the rabble rousers were saying that moshe got rich off the donation money to the mishkan, so he counted it to prove he didn't take anything.
The posuk says ויעשו בני ישראל ככל אשר צוה ה' את משה that the entire B'nai Yisroel did all that 'ה commanded Moshe.
The Ohr Hachaim says that even though only Betzalel & the chachmai lev did the construction on the mishkan, since everyone agreed that they should do it for them, its considered like everyone did it.- כל ישראל ערבים זה לזה. From here we also see that the Torah is a group effort. Everyone has to do his part, & in doing so, it's as if he did all the mitzvos.
The Ohr Hachaim proves it by saying that the only way the 613 mitzvos (which correspond to the 613 parts of a person's body) can be fulfilled is by one doing for the other, for there are some mitzvos that can only be done by kohanim or leviem or women, so the only way 613 mitzvos can be performed is if we're all connected & responsible for one another. Maybe this is also what the Torah is alluding to when it says Mishkan twice; that just like at the completion we were all together and unified, the way to get back the משכון is by being unified.
Just like עין הרע & שנאת חנם caused the destruction & started the problems, if we do the opposite & love one another, & work together like we did at the start, we can get back the bais hamikdash bimhaira b'yameinu!