that is arduous and demanding, yet make no profit; or you may think that he will make only a small profit, but he makes a great deal.

Thus, the specified payment is known either by explicit designation—its amount and description—or as an undivided share, that is, as a fractional portion.

“Such as returning a slave, finding lost property, sewing, or building a wall. Whoever performs it after learning of the offer becomes entitled to it. If a group performs it, they divide it among themselves. If he learns of it in the course of the work, he receives a proportionate share for the part he completes thereafter. …”

His statement, “such as returning a slave,” means returning a fugitive slave—that is, one who has run away from his master—where the master offers a reward to whoever brings him back. Similarly, if he offers a known reward to whoever brings him his lost child, this is permissible, because it is work. Although a free person is not, in principle, something that may be sold, this is not a sale of him; rather, it is bringing him back.

His statement, “finding lost property,” means returning lost property, namely property that has gone missing. This is like the expression, “I fed her straw and cold water,” meaning, “and gave her cold water to drink,” since water is not fodder. Lost property can only be returned when it is in the possession of someone who has found it and then returns it. What is meant here by returning lost property is finding it and bringing it to its owner.

His statement, “sewing,” means sewing a garment. For example, one might say, “Whoever sews for me a garment with such-and-such specifications will receive the known payment.” The cloth belongs to the customer, not the worker, and this is permissible. But if the material belongs to the worker, this is known to the scholars as istisnaʿ (a manufacturing contract), concerning which there is a difference of opinion. Some hold that it is not permissible, because it is not a salam contract (forward purchase): a salam contract requires deferred delivery, while this is not a specified item, since it is owed as a liability, and a description may not fully define it. The correct view, however, is that it is permissible, because it can be precisely defined by description, and people have practiced it from ancient times until the present.

His statement, “and building a wall,” means, for example, that he says, “Whoever builds this wall for me shall receive …”