Deuteronomy 4:31

4:31 (for he is a merciful God), he will not let you down or destroy you, for he cannot forget the covenant with your ancestors that he confirmed by oath to them.

Deuteronomy 29:13

29:13 Today he will affirm that you are his people and that he is your God, just as he promised you and as he swore by oath to your ancestors Abraham, Isaac, and Jacob.