1 Samuel 15:11; 1 Samuel 15:29; 1 Samuel 15:35

11 It repenteth me that I have set up Saul to be king: for he is turned back from following me, and hath not performed my commandments. And it grieved Samuel; and he cried unto the LORD all night.
29 And also the Strength of Israel will not lie nor repent : for he is not a man, that he should repent .
35 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.