The apparent meaning of al-Khiraqi’s words is that this [knowledge of the price's description] is not a condition, because he mentioned the conditions of Salam without mentioning it. This is one of the two opinions of al-Shafi’i, for it is a witnessed compensation (compensation for which the object is present), so there is no need to know its quantity, just like in sales of specific objects (a’yan). Ahmad’s statement only refers to non-specified (price), and there is no disagreement regarding the consideration of its qualities. Their evidence is invalidated by the contract of lease (ijara), for it is annulled by the destruction of the leased object, and there is no need with certainty to know the qualities. Furthermore, returning the like of the price is only due upon the annulment of the contract, not from the aspect of contracting it, and ignorance of that does not affect the contract, just as if he were to sell items sold by measure or weight. Moreover, the contract has already fulfilled its conditions, so it does not become void due to an assumed matter. Thus, according to the opinion that considers its qualities, it is not permissible to set the capital of the Salam as an asset whose qualities cannot be determined, such as jewels and other items in which Salam is not permissible. If they make it a Salam, the contract is void, and it must be returned if it is extant, or its value must be paid if it is known, should it be non-extant. If they disagree, the statement is that of the person receiving the Salam (muslam ilayhi), because he is the debtor. This is also the case if we rule on the validity of the contract and it is subsequently annulled. If they disagree regarding the item for which the Salam was paid—one says it is for one hundred mudds of wheat, and the other says it is for one hundred mudds of barley—they must mutually swear oaths and annul the contract. Al-Shafi’i, Abu Thawr, and the People of Opinion (Ashab al-Ra’y) said: This is just as if they disagreed regarding the price of an item sold.

Section: For any two types of property in which deferment (nasi’a) is prohibited, it is not permissible to pay Salam in one for the other, because a condition of Salam is deferment and postponement. Al-Khiraqi prohibited the sale of some commodities for others with deferment; therefore, according to his opinion, it is not permissible to use some as Salam for others. Ibn Abi Musa said: The capital of the Salam cannot be anything but currency (ayn) or silver (wariq). The Qadi said: This is the apparent meaning of Ahmad's words here. Ibn al-Mundhir stated: It was said to Ahmad: Does one pay in Salam items weighed for items measured, and items measured for items weighed?