The Messenger of Allah ﷺ forbade two transactions combined into one.
نهي رسول الله ﷺ عن بيعتين في بيعة.
No references are available.
Narrated by Tirmidhi (1231), Nasai (4632), and Ahmad (9584), and Ibn Hibban (4973) graded it sahih, as did Bayhaqi (5/343) and Ibn Jarud (600), all of them through various routes from Muhammad bin Amr, who said, "Abu Salama narrated to us, from Abu Hurairah," and he related it. Its chain is hasan because of Muhammad bin Amr, who is Ibn Alqama Laythi, for he is hasan al-hadith. This is how it was narrated by Abdul-Wahhab bin Ata, Ismail bin Jafar, Abdul-Aziz bin Muhammad Darawardi, Muaz bin Muaz, Abdah bin Sulayman, Yahya bin Saeed Qattan, and Yazid bin Harun, all of them from Muhammad bin Amr, with the same wording.Yahya bin Zakariya bin Abu Zaida differed from them, narrating it from Muhammad bin Amr, from Abu Salama, from Abu Hurairah, as a raised hadith with the wording, "Whoever sells two sales in one sale gets the lesser of the two prices, or it is riba." This was narrated by Abu Dawud (3461), Ibn Hibban (4974), Hakim (2/45), and Bayhaqi (5/343), all of them through the route of Yahya bin Zakariya, who related it. Hakim said, "Sahih according to the standard of Muslim."The meaning of the hadith, "It seems that this concerns a dispute over a specific thing, as if he had given him a dinar in advance for a measure of wheat due in a month, and when the term came due and he demanded the wheat, the debtor said to him, 'Sell me the measure that you are owed for two measures due in a month.' This is a second sale that has entered into the first sale, so it becomes two sales in one sale, and the two are reduced to the lesser of them, which is the original amount. If the two parties transact the second sale before cancelling the first, then they have both engaged in riba."As for the interpretation of his saying, "two sales in one sale," it has been said that its interpretation is that the seller says, "I sell it to you for a thousand in cash, or two thousand on credit, so accept whichever you wish." This is the interpretation of Shafii, and the reason for its prohibition is that the price increases with the extension of the term, which resembles riba. So said Khattabi. Some scholars stipulated that this applies when the acceptance remains ambiguous, but if the buyer accepts one of the two options specifically, it is permissible.It is related from Tawus that he said, "There is no harm in saying, 'This garment is ten in cash, or fifteen due in a month,' and then leaving it to the buyer to choose one of the two," meaning he chooses one of the two sales before they part, and this is permissible. Of this type is installment sale, which was not known before, and the majority of scholars have permitted it. The Permanent Committee for Issuing Fatwas in Saudi Arabia has issued a ruling permitting it under certain conditions, including specifying the deferred price, the number of installments, the amount of each installment, and other conditions, so that no dispute arises over it.The second interpretation is that the seller says, "I sell to you on condition that you sell to me," meaning that if the sale becomes binding for you from me, it becomes binding for me from you as well. This is an invalid sale.The third interpretation is that the seller says, "I sell you this garment for a hundred riyals on condition that you give me thirty dollars." But if he said, "Give me the equivalent of a hundred riyals in dollars at today's exchange rate," this would be permissible, just as Ibn Umar used to buy and sell in dinars and pay dirhams at the day's exchange rate, and this is not considered two sales in one sale.The fourth interpretation is that some have said that two sales in one sale is like someone selling a house and a car for a single price, but the correct view is that this is permissible, for it is simply a single transaction combining two items for a known price, as Khattabi said. However, if a dispute arises between the seller and the buyer, the entire sale is annulled, because the price of each item sold was not specified. And success comes from Allah.