My father, the grandfather of Ubaiyah bin Rafa’ah narrates: I said, O Messenger of Allah! Tomorrow we will encounter the enemy and we do not have any knife or similar tool. The Prophet (peace be upon him) said: Sacrifice it and quickly drain its life. Whatever causes blood to flow, and Allah's name was mentioned at the time of causing blood to flow, then eat it. Except that you do not use teeth or nails. I will inform you about this: the tooth is a bone and the nail is the knife of the Abyssinians.