Mishkat al-Masabih #3152

‘Amr b. Shu'aib, on his father’s authority, said his grandfather reported God’s Messenger as saying, “No descendant of Adam may make a vow about what he does not possess, or set free what he does not possess, or divorce what he does not possess.” Tirmidhi transmitted it, and Abu Dawud added, “or sell what he does not possess.”