He took Agag the king of the Amalekites alive, and utterly destroyed all the people with the edge of the sword.
For the Lord said, I remember the Amaleks that when you were trying to come into the land, they withstood you. And therefore God wants you to go down and utterly wipe out the Amaleks; every man, woman, child, animal. [Don't take anything back alive, utterly slay everything] ( 1 Samuel 15:2-3 ).