Deuteronomy 7:9-11

9Know therefore that the LORD your God is God; he is the faithful God, keeping his covenant of love to a thousand generations of those who love him and keep his commandments.

10But those who hate him he will repay to their face by destruction; he will not be slow to repay to their face those who hate him.

11Therefore, take care to follow the commands, decrees and laws I give you today.