the conditions of the leased property: it must be possible to deliver it to the lessee. This is due to the Prophet’s saying: “Do not sell what you do not possess.” (1) Leasing is a type of sale, and that which cannot be delivered is neither in one’s possession nor under one’s control, nor is one able to obtain it. It is also due to his prohibition of sales involving excessive uncertainty. (2) Leasing something that cannot be delivered involves excessive uncertainty, since its owner will lower the rent; otherwise, no one would lease it from him. If the lessee is able to obtain it, he gains; but if he is unable, he loses. This is a form of excessive uncertainty. Moreover, since leasing is a type of sale, just as we stipulate in a sale that the item sold must be deliverable, so too do we stipulate in a lease that the leased property must be deliverable.
His statement: “Thus, leasing an absconding slave is not valid,” meaning a slave who has run away from his master, and whose whereabouts are entirely unknown to him. Leasing such a slave is not valid, because he cannot be delivered. In that case, the lessee may either be able to take possession of him or not. If he is able to take possession of him, he gains; but if he is unable, he loses. This is because the rent for an absconding slave cannot be the same as the rent for a slave who is present: his rent will be reduced, and the lessee will regard himself as taking a risk. Thus, if we suppose that this slave is leased out per day