This is the rule of the school: “A ribā-based commodity may not be sold for another of its own kind when either both of them, or one of them, is accompanied by something of a different kind”—under any circumstances. Even if someone were to say: “If he sells one ṣāʿ of dates and one dirham for two dirhams, and the ṣāʿ is worth one dirham, why should we not regard the ṣāʿ as being in exchange for one dirham, and the dirham as being in exchange for the other dirham? There is then no ribā involved.” This is why, if he were to say, “I sold you this ṣāʿ for one dirham, and I exchanged this dirham with you for another dirham,” such an arrangement would be permissible. So what difference is there between saying, “I sold you one ṣāʿ and one dirham for two dirhams,” so long as the ṣāʿ is worth neither more nor less than one dirham?

The scholars, may Allah have mercy on them, said: This is in order to block the means, because the matter of ribā is grave; therefore, every avenue that may lead to it must be closed. For this reason, the Prophet, peace and blessings be upon him, prohibited the sale of al-ʿīnah, even though ribā may be remote in such a transaction (1).

The sale of al-ʿīnah is where a person sells something for a deferred price, then buys it back for cash at a lower price than that for which he sold it. The outward form of the transaction contains nothing objectionable, but it is prohibited lest it become a means of circumventing ribā: he gives the other party eighty dirhams, while one hundred dirhams remain owed by him. For this reason, we close every door that leads to ribā.

However, Shaykh al-Islam, may Allah have mercy on him, disagreed with this and said: If the unaccompanied item is greater than the item accompanied by something else, and this excess corresponds to that other item, then it is permissible and there is nothing wrong with it. Need may also call for it.