Rabbi Eliezer Hamodai calculated exactly how long the manna lasted after the death of Moses: seventy days. Not a rough estimate — a precise count, worked out from the calendar itself.
Moses died on the seventh of Adar. The Israelites still had manna stored in their vessels, and they continued eating from that supply. They consumed it for twenty-four remaining days of the first Adar, then thirty days of the second Adar (because that year was a leap year with an intercalated month), and finally sixteen days of Nisan. Add them up: twenty-four plus thirty plus sixteen equals exactly seventy days.
The manna then ceased "on the morrow" — the day after they first ate from the produce of the land of Canaan, as described in the book of Joshua. The miraculous bread stopped the moment it was no longer needed.
This calculation reveals something poignant about the transition from wilderness to homeland. The manna did not vanish the instant Moses died. God did not cut off His provision in a moment of grief. Instead, the supply tapered naturally, lasting precisely long enough to carry Israel across the Jordan and into a land where they could grow their own food. Seventy days — the same number associated with mourning and completion throughout Jewish tradition — served as a bridge between two eras. One form of sustenance faded only when another was ready to take its place.