Ahmad ibn Mani reported from Isma’il ibn Ibrahim, from Ayyub, from Amr ibn Shu’ayh who from his father and he from the grandfather of Amr ascending up to Abdullah ibn Amr that Allah’s Messenger (SAW) said, salaf. Wa Bai are not lawful . Also, two conditions in one sale are not allowed. Also, profit of what he is not a guarantor is not allowed. In the same way, it is not lawful to sell that which is not in one’s possession.”
[Ahmed 6683, Abu Dawud 3504, Nisai 4642, Ibn e Majah 2188]
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