Silver for gold is Riba (usury) unless exchanged on the spot; wheat for wheat is Riba unless exchanged on the spot; barley for barley is Riba unless exchanged on the spot; and dates for dates is Riba unless exchanged on the spot

Explanation

Mālik ibn Aws, the Tābi‘i, informs that he had gold dinars that he wanted to exchange with silver dirhams. Talhah ibn ‘Ubaydullāh (may Allah be pleased with him) said to him: Give us your dinars to see them. Then, after deciding to buy them, he said to him: Come later when our servant comes to give you the silver dirhams. This situation took place in the presence of ‘Umar ibn al-Khattāb (may Allah be pleased with him), who expressed his disapproval of such a transaction and swore that Talhah should either pay the silver now or give him back his gold that he took from him. He justified this by saying that the Messenger of Allah (may Allah's peace and blessings be upon him) mentioned that when selling silver for gold or vice versa, the exchange should be made immediately; otherwise, this will be a prohibited Riba-based transaction and an invalid sale. Thus, gold should not be sold for silver, and silver should not be sold for gold except hand to hand and with the exchange made on the spot. Moreover, wheat should not be sold for wheat, barley should not be sold for barley, and dates should not be sold for dates except like for like, weight for weight, measure for measure, hand to hand, and nothing thereof should be sold immediately for deferred payment, and it is impermissible for the two parties to depart before the exchange is made.

Benefits

• The types mentioned in this Hadīth are five: gold, silver, wheat, barley, and dates. If the sale involves items of the same type, then two conditions must be fulfilled to make it valid: the exchange should be made during the contract session, and they should be of the same weight, like gold for gold, or else it is Riba al-Fadl (usury of surplus). On the other hand, if the sale involves items of different types, like silver for wheat, then one condition must be fulfilled to make the contract valid, namely receiving the price during the contract session; otherwise, it is Riba an-Nasī’ah (usury of deferred payment).
• The contract session refers to the place where the sale is conducted, whether the two parties are sitting, walking, or riding, and departing refers to what is customarily known among people as a way of ending a meeting.
• The prohibition in this Hadīth includes all the types of gold, coined or not, and all the types of silver, coined or not.
• What is required when selling gold for silver should be applied to the coins of this current time, i.e., if one wants to exchange one coin for another, like exchanging one riyal for one dirham, the surplus is permissible if both parties agree; however, the exchange should be made during the sale transaction or the transaction will be invalid and it will be deemed as a prohibited Riba-based transaction.
• Riba-based transactions are impermissible, and the contract is invalid even if the two parties agree because Islam protects man's rights and the rights of society even if he waives them.
• Forbidding and preventing evil for whoever has the ability to do so.
• Mentioning the evidence when forbidding evil as what ‘Umar ibn al-Khattāb (may Allah be pleased with him) did.