Exodus 34:14-17

(for thou shalt worship no other god: for Jehovah, whose name is Jealous, is a jealous God); lest thou make a covenant with the inhabitants of the land, and they play the harlot after their gods, and sacrifice unto their gods, and one call thee and thou eat of his sacrifice; and thou take of their daughters unto thy sons, and their daughters play the harlot after their gods, and make thy sons play the harlot after their gods. Thou shalt make thee no molten gods.