The Book of Transactions (Kitab Al-Buyu`)

Muslim :: Book 10 : Hadith 3872

Abu Sa'id (Allah be pleased with him) reported: Dates were brought to Allah's Messenger (may peace be upon him), and he said: These dates are not like our dates, whereupon a man said: We sold two sa's of our dates (in order to get) one sa', of these (fine dates), whereupon Allah's Messenger (may peace be upon him) said: That is interest; so return (these dates of fine quality), and get your (inferior dates) ; then sell our dates (for money) and buy for us (with the help of money) such (fine dates).

Source materials are from the University of Southern California MSA site
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