Mishkat al-Masabih 2745

‘Amr b. Shu'aib, on his father’s authority, said his grandfather told that God’s Messenger forbade the type of transaction in which earnest money was paid (An arrangement by which the earnest-money was treated as part of the price if the deal was completed but was retained if it was not completed). Malik, Abu Dawud and Ibn Majah transmitted it.