Is buying dates and rice online with an upfront payment considered usury (riba)? Is immediate receipt at the store required after purchase and payment? Do cooked varieties of wheat (burr) and barley (sha'ir) fall under the ruling of the prophetic hadith: "Gold for gold, silver for silver, wheat for wheat, barley for barley, dates for dates, and salt for salt, like for like, hand to hand; whoever gives more or asks for more has engaged in usury, the receiver and the giver are equally culpable"? And what varieties are classified as "burr" (wheat) and "sha'ir" (barley) in our current era?

If a ribawi item is sold for another item of the same type—like gold for gold—then both excess (tafadhul) and deferral (ta'jil) are forbidden. However, if it is sold for an item of a different type—like gold for silver—then excess is permitted, but deferral is forbidden. As for selling ribawi items for monetary values—like wheat for gold—then both excess and deferral are permissible without dispute, because the Law has permitted salam (forward contracts), and the original understanding is that the capital is dirhams and dinars. If deferral were forbidden, the door to salam for weighed items would be closed. Therefore, buying dates and rice with cash does not require immediate possession (taqabud), and deferral is permissible.