Deuteronomy 7:1-4

CLV(i) 1 When Yahweh your Elohim brings you into the land where you are about to enter in order to tenant it, and He eases many nations out before your face, the Hittite, the Girgashite, the Amorite, the Canaanite, the Perizzite, the Hivite and the Jebusite, seven nations more numerous and substantial than you, 2 when Yahweh your Elohim gives them up before you, and you smite them, then you shall doom, yea doom them. You shall neither contract a covenant with them nor be gracious to them, 3 nor shall you intermarry with them. You shall not give your daughter to his son, and you shall not take his daughter for your son. 4 For it might take away your son from following after Me, and they might serve other elohim, and the anger of Yahweh would grow hot against you, and He would exterminate you quickly.