1 Samuel 15:31 (KJV)

And Samuel said unto Saul, I will not return with thee: for thou hast rejected the word of the LORD, and the LORD hath rejected thee from being king over Israel.

And as Samuel turned about to go away, he laid hold upon the skirt of his mantle, and it rent.

And Samuel said unto him, The LORD hath rent the kingdom of Israel from thee this day, and hath given it to a neighbour of thine, that is better than thou.

And also the Strength of Israel will not lie nor repent: for he is not a man, that he should repent.

Then he said, I have sinned: yet honour me now, I pray thee, before the elders of my people, and before Israel, and turn again with me, that I may worship the LORD thy God.

Then said Samuel, Bring ye hither to me Agag the king of the Amalekites. And Agag came unto him delicately. And Agag said, Surely the bitterness of death is past.

And Samuel said, As the sword hath made women childless, so shall thy mother be childless among women. And Samuel hewed Agag in pieces before the LORD in Gilgal.

Then Samuel went to Ramah; and Saul went up to his house to Gibeah of Saul.

And Samuel came no more to see Saul until the day of his death: nevertheless Samuel mourned for Saul: and the LORD repented that he had made Saul king over Israel.