Musnad Ahmad 27:1396

Waki' narrated to us, Al-'Umari narrated to us, from Az-Zuhri, from Abu Bakr ibn 'Ubayd Allah ibn 'Abd Allah ibn 'Umar, from Ibn 'Umar, who said: The Messenger of Allah (may Allah bless him and grant him peace) said: "If one of you eats or drinks, let him not eat with his left hand, and let him not drink with his left hand, for indeed, the Shaytan eats and drinks with his left hand."