Sahih Bukhari
Food, Meals
Volume: 007 / Book Number: 065 / Hadith Number: 319
Narrated 'Amr bin Umaiyya
that he saw the Prophet holding a shoulder piece of mutton in his hand and cutting part of it with a knife. Then he was called for the prayer whereupon he put down the shoulder piece and the knife with which he was cutting it, and then stood for prayer without performing ablution again.