Musannaf Ibn Abi Shayba 19:507

Abu Bakr narrated to us, he said: Muhammad ibn Bakr narrated to us, from Ibn Jurayj, from Ikrimah ibn Khalid: He said: A thief who had confessed was brought to Umar. Umar said, "I see the hand of a man who is not a thief." The man said, "By Allah, I am not a thief." So Umar released him and did not cut his hand.