Deuteronomy 31:3-6

3The 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. 4And the Lord will do to them what he did to Sihon and Og, the kings of the Amorites, whom he destroyed along with their land. 5The Lord will deliver them to you, and you must do to them all that I have commanded you. 6Be strong and courageous. Do not be afraid or terrified because of them, for the Lord your God goes with you; he will never leave you nor forsake you.”