Musnad Abu Ya'la al-Mawsili 153:170

Abu Khaythama narrated to us, Sufyan ibn 'Uyaynah narrated to us, from al-Zuhri, from Abu Bakr ibn 'Abd Allah, from his grandfather, from the Prophet (may Allah bless him and grant him peace), who said: "If one of you eats, let him eat with his right hand, and if he drinks, let him drink with his right hand, for indeed the devil eats with his left hand and drinks with his left hand." Zuhayr said: "He is [Ibn] 'Umar."