The Book of Transactions (Kitab Al-Buyu`)

Muslim :: Book 10 : Hadith 3646

Ibn Umar (Allah be pleased with them) reported Allah's Messenger (may peace be upon him) as saying: He who buys foodgrain should not sell that before taking possession of it. He (the narrator) said: We used to buy foodgrain from the caravans in bulk, but Allah's Messenger (may peace be upon him) forbade us to re-sell that until we had shifted it to some other place.

Source materials are from the University of Southern California MSA site
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