Deuteronomy 7:2-4

2The Lord your God will put those people under your power so that you win against them. When that happens, you must destroy them completely as a gift to God. Do not make any agreement with them to keep them safe. Do not be kind to them.

3You must not marry any of these people. Do not let your daughters marry their sons. Do not take their daughters to marry your sons.

4If that happens, your children may turn away from the Lord. They will start to worship other gods. Then the Lord will be very angry with you. He will immediately destroy you.