Deuteronomy 25:17-19

17“Remember what Amalek did to you along the way as you came out from Egypt—

18how he happened upon you along the way and attacked those among you in the rear, all the stragglers behind you, when you were tired and weary—he did not fear God.

19Now when Adonai your God grants you rest from all the enemies surrounding you in the land Adonai your God is giving you as an inheritance to possess, you are to blot out the memory of Amalek from under the heavens. Do not forget!