Deuteronomy 31:1-3

Then Moses went out and spoke these words to all Israel: “I am now a hundred and twenty years old and I am no longer able to lead you. The LORD has said to me, ‘You shall not cross the Jordan.’ The LORD your God himself will cross over ahead of you. He will destroy these nations before you, and you will take possession of their land. Joshua also will cross over ahead of you, as the LORD said.