Do Our Best
Regarding the completion of the construction of the Mishkan, there is a Midrash that says that Moshe Rabbeinu had trouble actually getting the thing to stand. In actuality, the Mishkan stood because Hashem wanted it to stand.
There is a very important message here. We must remember that in many ways, we are just going through the motions in what we do. Everything depends on Hashem making things happen.
It is not up to us to complete a given task. But it is our responsibility to do everything in our power to achieve our goals. We can only hope that we realize the outcome we are hoping to accomplish.
Rabbi Twerski adds that this is also true of parenting. We have a responsibility to do our best to give the best to our children. We must put them in the best environment possible so that they grow up as proud, religious Jews. But there are no guarantees.
It is not necessarily the fault of the parents, if the children go off the Derech. Avraham had Yishmael and Yitzchak had Eisav. There are no simple formulas in life. We just need to do the best that we can. The results might be the creation of our own holy sanctuary that will stand as proudly as the Mishkan.