Deuteronomy 13:17-18

17Nothing from that which is put under the ban (designated for destruction) shall cling to your hand, so that the Lord may turn away from His burning anger and show mercy to you, and have compassion on you and make you increase, just as He swore to your fathers,

18because you have listened to and obeyed the voice of the Lord your God, keeping all His commandments which I am commanding you today, and doing what is right in the eyes of the Lord your God.