the item sold is a slave, and the purchaser stipulates an option period of one week. During that week, the slave earns money by buying and selling, earning, for example, one thousand dirhams during the week. The thousand belongs to the purchaser, because earnings are separate increase.

Suppose this slave was purchased while emaciated, because his seller would feed him one meal and deprive him of another, so that he had no flesh on him. Then he comes into the purchaser’s possession, finds whatever food Allah wills and peace of mind, and becomes fat within a week. This increase belongs to the seller, because it is subsidiary to the original asset and cannot be separated from it. This is the view adopted by the author.

There is, however, another narration from Imam Ahmad: connected increase belongs to the one in whose ownership it arose. This was the view preferred by Shaykh al-Islam Ibn Taymiyyah, may Allah have mercy on him, who said: “This resulted from the purchaser’s efforts while it was in his ownership,” and “entitlement to yield follows liability” (1)—meaning that whoever bears liability for something is entitled to its yield. Connected increase may be more valuable than separate increase, in which case it belongs to the purchaser. If it belongs to the purchaser and the sale is then rescinded, the slave is assessed at the time of the contract, when he was emaciated, and at the time the sale is rescinded, when he is vigorous, ruddy, radiant, and fat. The difference is half the value, so half the value belongs to the purchaser. But if the seller says, “I will not accept this; take your connected increase,” what are we to do? Are we to do as Solomon did and say, “Bring the knife,” or what should we do? We say: you must accept it; there is no alternative.

His statement, “It is prohibited and invalid for either of them to dispose [of it],” assigns two rulings to disposal: prohibition and invalidity. The expression “it is prohibited” differs from the expression “it is invalid,” because