He is a Jealous God

Now, I am making a contract. I will do wonders before your people which have not been created in all the earth or in all of the nations. All the people among whom you are will see the work of the Eternal, because what I will do with you, it is fearful. Safeguard for yourself that which I command you today. Here, I am driving out from before you the Amorite, the Canaanite, the Hittite, the Perizzite, the Hivite and the Jebusite. Be on guard yourself or you may make a treaty with the inhabitant of the land to which you come. Perhaps, he will be a trap in your midst. Therefore, you are to demolish their alters, break their statues and cut their groves, because you may not bow to another god, because the Eternal - his name is jealous. He is a jealous God. Perhaps, you would make a treaty with the inhabitants of the land. They solicit their gods and sacrifice to their gods. He would call on you. You would eat from his sacrifice. You would take from his daughters for your sons. His daughters solicit their gods. Your sons would solicit their gods. Do not make molten gods for yourself! - Exodus 34:10-17