Deuteronomy 7:8-10

8 but because the LORD loved you and because he would keep the oath which he had sworn unto your fathers, has the LORD brought you out with a mighty hand and ransomed you out of the house of bondage from the hand of Pharaoh, king of Egypt.

9 Know, therefore, that the LORD thy God, he [is] God, the faithful God, who keeps covenant and mercy with those that love him and keep his commandments to a thousand generations

10 and repays him that hates him to his face, to destroy him; he will not be slack to him that hates him; he will repay him to his face.