Deuteronomy 7:9, 12-13

So know that the LORD your God is God, the faithful God. He will keep his agreement of love for a thousand lifetimes for people who love him and obey his commands.

If you pay attention to these laws and obey them carefully, the LORD your God will keep his agreement and show his love to you, as he promised your ancestors. He will love and bless you. He will make the number of your people grow; he will bless you with children. He will bless your fields with good crops and will give you grain, new wine, and oil. He will bless your herds with calves and your flocks with lambs in the land he promised your ancestors he would give you.