Narrated Rafi` bin Khadij: While we were with the Prophet. on a journey, one of the camels ran away. A man shot it with an arrow and stopped it. The Prophet said, Of these camels some are as wild as wild beasts, so if one of them runs away and you cannot catch it, then do like this (shoot it with an arrow). I said, O Allah's Apostle! Sometimes when we are in battles or on a journey we want to slaughter (animals) but we have no knives. He said, Listen! If you slaughter the animal with anything that causes its blood to flow out, and if Allah's Name is mentioned on slaughtering it, eat of it, provided that the slaughtering instrument is not a tooth or a nail, as the tooth is a bone and the nail is the knife of Ethiopians.