Deuteronomy 20:17-18

Leeser(i) 17 But thou shalt utterly devote them; namely, the Hittites, and the Emorites, the Canaanites, and the Perizzites, and the Hivites, and the Jebusites; as the Lord thy God hath commanded thee; 18 In order that they may not teach you to do in accordance with all their abominations, which they have done unto their gods; and ye would thus sin against the Lord your God.