The LORD your God Himself will cross over ahead of you. He will destroy these nations before you, and you will dispossess them. Joshua will cross ahead of you, as the LORD has said.
3 The Lord thy God, he will go over. By no ordinary consolation does he encourage their minds to renewed alacrity, because they should experience, even when he was dead, the unceasing favor of God. Hence we gather a lesson of especial usefulness, that whenever God raises up to us men endowed with excellent gifts, He is wont so to make use of their labors...
Moses could not cross Jordan himself, yet he would not abandon Israel without a word of encouragement. Though Joshua would lead them in battle, they would miss Moses interceding for them on the hill. But God had set His limit: his time to serve was finished, and he acquiesced, for what man should desire to live longer than God has work for him to do?
AI summary
Commenting on Deuteronomy 31:1-8
And the Lord shall do unto them as he did unto Sihon, and to Og, kings of the Amorites,.... Deliver them up into their hands; see the history of this in Num 21:10, and unto the land of them whom he destroyed; put them into the possession of the land of Canaan, as they were now in possession of the land of those two kings he destroyed by them.