Mukhtasar Bukhari (Abridged) 1277 — One who joins jihad for wages

Sayyiduna Ya'la bin Umayyah (may Allah be pleased with him) says that I had hired a man, and he fought with another man. One of them bit the other's hand with his mouth. The other pulled his hand out of his mouth, and his front teeth fell out. Then he came to the Prophet (peace and blessings of Allah be upon him). The Prophet (peace and blessings of Allah be upon him) did not award him compensation for the teeth and said: "Would he have left his hand in your mouth so that you could chew it, just as a camel chews greenery?"