Deuteronomy 31:3-5

Jehovah thy God, he will go over before thee; he will destroy these nations from before thee, and thou shalt dispossess them: and Joshua, he shall go over before thee, as Jehovah hath spoken. And Jehovah will do unto them as he did to Sihon and to Og, the kings of the Amorites, and unto their land; whom he destroyed. And Jehovah will deliver them up before you, and ye shall do unto them according unto all the commandment which I have commanded you.