Deuteronomy 7:3-5

3Do not intermarry with them. Do not give your daughters to their sons or take their daughters for your sons, 4because they will turn your sons away from following Me to serve other gods. Then the anger of the LORD will burn against you, and He will swiftly destroy you.

5Instead, this is what you are to do to them: tear down their altars, smash their sacred pillars, cut down their Asherah poles, and burn their idols in the fire.