1 Samuel 15:17-21

So Samuel said, “Is it not true, though you were insignificant in your own eyes, that you became the head of the tribes of Israel? For the Lord anointed you as king over Israel.

And the Lord sent you on a mission, and said, ‘Go and completely destroy the sinners, the Amalekites, and fight against them until they are eliminated.’

Why then did you not obey the voice of the Lord? Instead, you loudly rushed upon the spoils and did what was evil in the sight of the Lord!”

Then Saul said to Samuel, “I did obey the voice of the Lord, for I went on the mission on which the Lord sent me; and I have brought Agag the king of Amalek, and have completely destroyed the Amalekites.

But the people took some of the spoils, sheep and oxen, the choicest of the things designated for destruction, to sacrifice to the Lord your God at Gilgal.”