1 Samuel 15:9, 11

But Saul and the people spared Agag and the best of the sheep and of the oxen and of the fattened calves and the lambs, and all that was good, and would not utterly destroy them. All that was despised and worthless they devoted to destruction.

“I regret that I have made Saul king, for he has turned back from following me and has not performed my commandments.” And Samuel was angry, and he cried to the LORD all night.