and the report transmitted by Sahnūn states: “If the commodity is still subject to restitution, the sale is annulled.” This view is difficult to sustain, so it has been explained as referring to a case in which the original seller knew of their arrangement.
As for the third case, it is where he says, “Buy it for me for twelve on deferred payment, and I will purchase it from you for ten in cash.” This too is unlawful and impermissible. The objection is that he has hired the person instructed to purchase the commodity for him in exchange for lending him ten dinars, which he gives him to use until the payment falls due, when he returns them. The person giving the instruction is therefore bound to purchase the commodity for twelve on deferred payment. The person instructed must not receive the ten in cash from him immediately; if the former has already paid them to him, he must return them rather than retain them until the due date. In this case, he is entitled, by agreement, to the customary fee for such work, however much it amounts to.
As for the fourth case, it is where he says, “Buy such-and-such a commodity for ten in cash, and I will purchase it from you for twelve in cash.” Mālik’s position on this varied. On one occasion, he permitted it provided that both sales were for immediate payment and payment was actually received. On another, he disapproved of it because they had negotiated over the commodity before it became the property of the person instructed.
As for the fifth case, it is where he says, “Buy such-and-such a commodity for me for ten in cash, and I will purchase it from you for twelve on deferred payment.” This too is impermissible, but there is disagreement over its consequences if it takes place. Sahnūn narrated from Ibn al-Qāsim, who also attributed it to Mālik, that the person giving the instruction is bound to purchase it for twelve on deferred payment. This is because the purchaser would have borne the loss had the commodity perished in his possession before the person giving the instruction purchased it from him. Moreover, the person giving the instruction would have been entitled to decline to take it after the person instructed had purchased it. Nevertheless, he recommended that the person instructed exercise scrupulous caution and take from the person giving the instruction no more than the amount he had paid for it.
Ibn Habīb said: “The second sale is annulled if the commodity is still available, and it is returned to the person instructed. If it is no longer subject to restitution, its value on the day the person giving the instruction took possession of it becomes payable immediately, as is done with an unlawful sale. This is because there was a prior understanding to sell it before it became the property of the person instructed, so the transaction involved selling what one does not possess.”
As for the sixth case, it is where he says to him, “Buy it for yourself for twelve on deferred payment, and I will purchase it from you for ten in cash.” Sahnūn also narrated from Ibn al-Qāsim that the sale is not annulled once the commodity is no longer subject to restitution, and that the person giving the instruction owes only the ten. He considered it preferable, however, for him to pay the remaining five as well,