Why did Israel have to wander through the desert for forty years?
The people complain and ask to return to Egypt, to which God responds with a word of judgment: a forty-year stay in the wilderness, time for the present generation to die out completely. Among the spies, only Caleb was faithful and will be spared the punishment. This forty-year period marks not only a chronological interlude in the wilderness journey, but a theological one as well. The old generation will die, and God will begin anew with a new people (even a new census, chapter 26). Here we see an instance of what will become the essential biblical theme of death and renewal or death and resurrection. Sin and rebellion produces death; but out of death, God makes a new thing.