Matthew Henry Commentary 1 Samuel 15:24-31

"And Saul said unto Samuel, I have sinned; for I have transgressed the commandment of Jehovah, and thy words, because I feared the people, and obeyed their voice. Now therefore, I pray thee, pardon my sin, and turn again with me, that I may worship Jehovah. And Samuel said unto Saul, I will not return with thee; for thou hast rejected the word of Jehovah, and Jehovah hath rejected thee from being king over Israel. And as Samuel turned about to go away, [Saul] laid hold upon the skirt of his robe, and it rent. And Samuel said unto him, Jehovah hath rent the kingdom of Israel from thee this day, and hath given it to a neighbor 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 honor me now, I pray thee, before the elders of my people, and before Israel, and turn again with me, that I may worship Jehovah thy God. So Samuel turned again after Saul; and Saul worshipped Jehovah." — 1 Samuel 15:24-31 (ASV)

There were several signs of hypocrisy in Saul's repentance.

1. He pleaded with Samuel only, and seemed most anxious to maintain a good standing in his opinion and to gain his favor.
2. He made excuses for his fault, even when confessing it; that is never the way of a true penitent.
3. His entire concern was to save his reputation and preserve his influence with the people.

Men are fickle and change their minds, feeble and cannot carry out their purposes; something unforeseen happens by which their plans are disrupted. But with God it is not so. The Strength of Israel will not lie.