Musnad Ahmad 5:334

Abdullah narrated to us, Suwayd ibn Sa’id al-Harawi narrated to me, Yahya ibn Zakariya ibn Abi Za’idah narrated to us, from Ibn Jurayj, from al-Hasan ibn Muslim, from Mujahid, from ‘Abd al-Rahman ibn Abi Layla, from ‘Ali, who said: The Messenger of Allah (may Allah bless him and grant him peace) sent me regarding the sacrificial animals (al-budn). He said: "Do not give the butcher anything from them."