Deuteronomy 31:1-3

And Moses went and spake these words unto all Israel. And he said unto them, I am an hundred and twenty years old this day; I can no more go out and come in: also the LORD hath said unto me, Thou shalt not go over this Jordan. The LORD thy God, he will go over before thee, and he will destroy these nations from before thee, and thou shalt possess them: and Joshua, he shall go over before thee, as the LORD hath said.