Commentary :
Allah, Exalted is He, has deemed buying and selling lawful for His Muslim servants, but deemed Ribaa (i.e., interest, usury) unlawful. He Says (what means): {… they said, ”rade is [just] like Ribaa." But Allah has permitted trade and has forbidden Ribaa (interest).} [Quran 2:275].
In this hadeeth, the Prophet ﷺ forbids forms of Ribaa involved in the sale of gold and silver, and teaches Muslims the lawful ways of buying and selling gold and silver, to avoid falling into what is unlawful. He ﷺ said: “Do not sell gold for gold unless equal in weight, nor silver for silver unless equal in weight”, meaning that gold may be sold for gold if the exchanged items are equal in weight, and the same goes for silver.
By analogy, the same ruling applies to all sales transactions in which the exchanged commodities share the same ‘Illah (i.e., the underlying legal reason that necessitates the effective cause of the ruling, which then leads to its enactment), which is being used as currency (i.e., Thamaniyyah) in the case of gold and silver. Likewise, the ruling applies to whatever is being used as currency, like paper money, and is subject to Ribaa in such sale transactions as well.
Another requirement is Taqaabudh (i.e., immediate exchange and reciprocal taking possession of the purchased commodity and its monetary equivalent by the buyer and seller respectively in the contracting session). The immediate exchange of the two items in the contracting session is required, and it is impermissible to delay the submission of any of them, given the relevant hadeeths. It was reported in Saheeh Al-Bukhaaree and Saheeh Muslim that the Prophet ﷺ said: “A barter of gold for gold is Ribaa except if they are exchanged hand to hand (i.e., on the spot) and are equal in amount.” This means that the two parties must exchange the two commodities on the spot before leaving the contracting session.
However, in the event of a barter of different commodities, like selling gold for silver for example, there may be a difference in weight. The Prophet ﷺ said: “…but you could sell gold for silver or silver for gold as you like,” meaning that there is no harm if the exchanged commodities differ in weight in this case, provided that they are exchanged hand to hand in the contracting session; the Prophet ﷺ said: “If the exchanged commodities differ in kind, sell as you wish as long as payment is made hand to hand on the spot.” [Muslim].
It was also narrated that the Prophet ﷺ said: “… and do not sell that (gold or silver) which is not present (at the time of the transaction) for that (gold or silver) which is present.” [Al-Bukhaaree]. This is to avoid falling into Ribaa Al-Nasee’ah, which is an increase in the loan or due amount in return for a delay in payment.
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