1 Samuel 15:10-21
10The word of the LORD came to Samuel: 11I regret that I made Saul king, for he has turned back from following me, and has not carried out my commands. Samuel was angry; and he cried out to the LORD all night. 12Samuel rose early in the morning to meet Saul, and Samuel was told, "Saul went to Carmel, where he set up a monument for himself, and on returning he passed on down to Gilgal." 13When Samuel came to Saul, Saul said to him, "May you be blessed by the LORD; I have carried out the command of the LORD." 14But Samuel said, "What then is this bleating of sheep in my ears, and the lowing of cattle that I hear?" 15Saul said, "They have brought them from the Amalekites; for the people spared the best of the sheep and the cattle, to sacrifice to the LORD your God; but the rest we have utterly destroyed." 16Then Samuel said to Saul, "Stop! I will tell you what the LORD said to me last night." He replied, "Speak."
17Samuel said, "Though you are little in your own eyes, are you not the head of the tribes of Israel? The LORD anointed you king over Israel. 18And the LORD sent you on a mission, and said, ‘Go, utterly destroy the sinners, the Amalekites, and fight against them until they are consumed.’ 19Why then did you not obey the voice of the LORD? Why did you swoop down on the spoil, and do what was evil in the sight of the LORD?" 20Saul said to Samuel, "I have obeyed the voice of the LORD, I have gone on the mission on which the LORD sent me, I have brought Agag the king of Amalek, and I have utterly destroyed the Amalekites. 21But from the spoil the people took sheep and cattle, the best of the things devoted to destruction, to sacrifice to the LORD your God in Gilgal."