The Book Pertaining to the Oath, for Establishing the
Responsibility of Murders, Fighting, Requital and Blood-Wit (Kitab
Al-Kitab Al-Qasama wa'l-Muharaba wa'l-Qisas wa'l-Diyat) 
Muslim :: Book 16 : Hadith 4164
'Alqama b. Wa'il reported on the authority of his-father: While I was sitting in the company of Allah's Apostle (may peace be upon him), a person came there dragging another one with the help of a strap and said: Allah's Messenger, this man has killed my brother. Allah's Messenger (may peace be upon him) said to him: Did you kill him? And the other man said: (In case he did not make a confession of this, I shall brine, a witness against him). He (the murderer) said: Yes, I have killed him. He (the Holy Prophet) said: Why did you kill him? He said: I and he won striking down the leaves of a tree and he abused me and enraged me, and to I struck his head with an axe and killed him, whereupon Allah's Messenger (may peace be upon him) said: Have you anything with you to pay blood-wit on your behalf? He said: I do not possess any property but this robe of mine and this axe of mine. He (the Holy, Prophet) said: Do you think your people will pay ransom for you? He said: I am more insignificant among my people than this (that I would not be able to get this benefit from my tribe). He (the Holy Prophet) threw the strap towards him (the claimant of the blood-wit) saying: Take away your man. The man took him away, and as he returned, Allah's Messenger (may peace be upon him) said: If he kills him, he will be like him. He returned and said: Allah's Messenger, it has reached me that you have said that" If he killed him, he would be like him." I caught hold of him according to your command, whereupon Allah's Messenger (may peace be upon him) said: Don't you like that he should take upon him (the burden) of your sin and the sin of your companion (your brother)? He said: Allah's Apostle, why not? The Messenger of Allah (may peace be. upon him) said: If it is so, then let it be. He threw away the strap (around the offender) and set him free.