Never, Sometimes, Always
In Parashat Ki Tavo, Moshe instructs the people to do an extensive ceremony when they come to a specific mountain after they enter the land. Many aspects of this ceremony are reminiscent of Sinai. A mountain, words of Torah written on stones, building an altar and offering sacrifices. It looks like a reenactment of entering into a covenant with God at Sinai and all of the obligations entailed by berit. But why is there a need to reenact Sinai? Wasn’t that one-time event powerful enough on its own to solidify entry into covenant for all future generations?