Deuteronomy 31:1-4

So Moses went and spoke these words to all Israel.

And he said to them, “I am 120 years old today; I am no longer able to go out and come in, and the Lord has told me, ‘You shall not cross this Jordan.’

It is the Lord your God who is going to cross ahead of you; He Himself will destroy these nations before you, and you shall dispossess them. Joshua is the one who is going to cross ahead of you, just as the Lord has spoken.

And the Lord will do to them just as He did to Sihon and Og, the kings of the Amorites, and to their land, when He destroyed them.