God promises to protect His people if they exterminate the Canaanites and their idols. This requirement is because of the latter’s wickedness, not Israel’s righteousness. The Hebrews will also perish if they forget God.
Note Deuteronomy 7:2; 12:2–3; 14:21: Canaanites, Amorites, Hittites, Girgashites, Hivites and Jebusites were iniquitous people groups descended from Canaan, the son of Ham (Genesis 10:15–17; 15:16). The Perizzites, hill dwellers, may also have been related. Their religion was crude, bestial and materialistic, involving multiple gods, cult prostitutes and sexual deviation (Leviticus 18:23–25; 20:23; Deuteronomy 20:18). A common cultic practice was to worship under selected green trees, which evil spirits would inhabit (1 Kings 14:23 is one of many references). Part of the Canaanite religious practice was cooking a young goat in its mother’s milk (Deuteronomy 16:21).