Exodus 34:14-16

14Do not worship any other god, for the Lord, whose name is Jealous, is a jealous God. 15“Be careful not to make a treaty with those who live in the land; for when they prostitute themselves to their gods and sacrifice to them, they will invite you and you will eat their sacrifices. 16And when you choose some of their daughters as wives for your sons and those daughters prostitute themselves to their gods, they will lead your sons to do the same.