The Mekhilta records an alternative explanation for why Israel went three days without water. According to this view, the problem was not the desert at all. The problem was their canteens.
When the Israelites crossed the Red Sea, the waters had parted into walls on either side, creating a dry corridor through the deep. Between the clefts of these walls, the people had filled their vessels with water — fresh, miraculous water from the divided sea itself. They carried this supply with them into the wilderness, expecting it to last.
But after three days, it ran out. The water they had collected between the sea's clefts gave out, and suddenly the entire camp was dry. "Without finding water" meant something very specific: even in their own vessels, there was nothing left.
Jeremiah provides the prophetic parallel (Jeremiah 14:3): "Their nobles sent their youths for water. They came to the cisterns, but found no water. They returned, their vessels empty." The image is identical — vessels that once held water, now bone-dry. The cisterns that should have provided are barren. The containers that should have sustained are hollow.
This reading adds a layer of irony to the wilderness narrative. The very sea that saved Israel also gave them a false sense of security. They thought they had prepared. They thought they had enough. But miraculous provisions do not last forever, and the water from between the walls of the Red Sea was no exception.