Exodus 23:33
They shall not dwell in thy land, lest they make thee sin against me: for if thou serve their gods, it will surely be a snare unto thee. They shall not dwell in thy land, lest they make thee sin against me: for if thou serve their gods, it will surely be a snare unto thee.
They shall not be allowed to go on dwelling in the land, for the idolatrous peoples and nations of Canaan were not to remain among Israel lest their presence draw Israel into sin against God by serving their gods, and that service would surely become a snare to Israel. The failure to drive those nations out and to keep separate from them, but instead to associate with them, brought idolatry and lasting harm.
The prohibition stands as part of the conditions of the promised blessing, which required obedience to God, rejection of other gods, and the overthrow of idols and the removal of all idolatry. Obedience and keeping the commandments were made the condition, with the promise that if Israel agreed to keep them they would be as kings and priests to God and He would communicate with them, a reward still to be given now. It is a clear warning of the Lord against idolatry, joined to the command to make no covenant with those nations or their gods and to destroy their idols, because even costly and beautiful images could tempt to reverence.
The instruction belongs to what was given on the mount in Exodus 19-24, written in a book to guard against doing injustice and to guide dealings with one another, and it was given by Christ Himself, the same Teacher who afterward spoke in human flesh; it is to be studied, set before the people, and obeyed now just as fully as by Israel in the days of Moses. Moses was to gather up the truth, light, and grace given from Sinai and carry it out in practice before the people, giving an example of obeying the whole of the commandments with a heart to obey them. Israel vowed with voice and with hands lifted to heaven to comply, yet while Moses was away broke the condition by making the calf in idolatry, and then faced a test of loyalty to the side of Moses in which the disloyal perished; this shows that God tests by His Word and that obedience gives strength of character under every temptation so as not to lose hold upon God.