Building and Yielding
Before explaining how to build the Mishkan Moshe begins with Shabbos to show that building the Mishkan doesn't override Shabbos. Rebbe Nachman asks: why would we ever think building the Mishkan overrides Shabbos - nothing overrides Shabbos except saving a life!
The purpose of the Mishkan and of Shabbos are the same - to bring the Jewish people closer to Hashem. We create a domicile for the Divine in this world and He rests therein. The essence of Shabbos is the creation of a framework in which to bring Hashem into our lives. The greatness of Shabbos is in what we don't do, that we don't create. Is true deveykus achieved via action or abstention, via building or yielding? Shabbos overrides the Mishkan because the Shabbos model of clinging to Hashem comes first.
Provided courtesy of rabbisilber.com