Musnad Ahmad 33:10

Yahya narrated to us, Sufyan narrated to us, from Abu al-Zubayr, from Jabir, who said: "The Messenger of Allah (may Allah bless him and grant him peace) forbade that a man should eat with his left hand, or walk in one sandal, or sit in an *ihtiba* (a posture of sitting with the knees drawn up to the chest) while wearing a single garment, or wrap himself in the *al-samma'* (a style of wrapping the body in a garment that leaves no opening for the arms)."