Yazid bin Safwan bin Umayyah narrates that a thief came to his father (Sayyiduna Safwan bin Umayyah, may Allah be pleased with him) while he was asleep, and pulled the sheet out from under his head. He woke up and caught him, and brought him to the Prophet (peace and blessings be upon him). He (peace and blessings be upon him) ordered that his hand be cut off. He said: "O Messenger of Allah, I have forgiven him for it." He (peace and blessings be upon him) said: "Why did you not do this before bringing him to me? When one of the prescribed punishments (hudud) of Allah reaches the ruler, he carries it out."
Hadith Referenceالمعجم الكبير للطبراني / باب الصاد / 7305