Sayyiduna Ya'la bin Umayyah (may Allah be pleased with him) narrates: I participated in the Battle of Tabuk with the Prophet (peace and blessings of Allah be upon him). To me, this is my best deed. I had a servant who fought with another man. One of them bit the other's hand. When he pulled his finger away, the biter's front teeth broke. He came to the Prophet (peace and blessings of Allah be upon him), and the Prophet (peace and blessings of Allah be upon him) declared his teeth to be wasted. The narrator says: I think the narrator named Safwan also narrated these words: The Prophet (peace and blessings of Allah be upon him) said: "Would he have left his hand in your mouth so that you could chew it like a camel chews?"