English translation
2136. Narrated Ibn ‘Umar رضي الله عنهما: The Prophet ﷺ said, “The buyer of foodstuff should not sell it before it has been measured for him.” Ismā‘īl narrated instead, “He should not sell it before receiving it.” (1) (Ch. 55) If one buys foodstuff for one pound and sells it for two pounds before receiving it from the first seller, the transaction is illegal for it is usurious, for it is as if one bartered gold for gold, one pound for two pound. It is also the sale of something absent for something present which is also illegal. (Al-Qaṣṭalāni Vol. 4).