Sahih Muslim Book 23, Hadith Number 5105.

Chapter : Showing honour to the guest and the merit of making of sacrifice for him.

‘Abd al-Rahman b. Abu Bakr reported: We were one hundred and thirty (persons) with Allah’s Apostle (may peace be upon him). Allah’s Apostle (may peace be upon him) said: Does any one of You possess food? There was a person with (us) who had a sa’ of flour or something about that, and it was kneaded. Then a tall polytheist with dishevelled hair came driving his flock of sheep. Thereupon Allah’s Apostle (may peace be upon him) said: Would you like to sell it (any one of these goats) or offer it as a gift or a present? He said: No, (I am not prepared to offer as a gift), but I would sell it. He (the Holy Prophet) bought a sheep from him, and it was slaughtered and its meat was prepared, and Allah’s Messenger (may peace be upon him) commanded that its liver should be roasted. He (the narrator) said: By Allah, none among one hundred and thirty persons was left whom Allah’s Messenger (may peace be upon him) had not given a part out of her liver; if anyone was present he gave it to him, but if he was absent it was set aside for him. And he (the Holy Prophet) filled two bowls (one with soup and the other with mutton) and we all ate out of them to our hearts’ content, but (still) some part was (left) in (those) two bowls, and I placed it on the camel-(or words to the same effect).