Deuteronomy 25:17-19
Treatment of the Amalekites
25:17 Remember what the Amalekites did to you on your way from Egypt,
25:18 how they met you along the way and cut off all your stragglers in the rear of the march when you were exhausted and tired; they were unafraid of God.
25:19 So when the Lord your God gives you relief from all the enemies who surround you in the land he is giving you as an inheritance, you must wipe out the memory of the Amalekites from under heaven – do not forget!