1 Samuel 15:20-21

20Saul said to Samuel, ‘I did obey the Lord! I did the job that the Lord told me to do. I killed all the Amalekites and I brought back Agag, their king.

21But the army did not kill all the sheep and cows that they took from the Amalekites. They brought the best animals to offer as a sacrifice to the Lord your God at Gilgal.’