It is possible that it is obligatory upon the owner of the physical entity. This is what Al-Sharif Abu Ja'far mentioned as a school of thought for Ahmad, and it is the view of Abu Thawr, and the apparent school of Al-Shafi'i; because maintenance follows the physical entity, so it should be upon its owner, like a leased slave, and as if he did not have (16) a benefit. Al-Sharif said: And because the fitra (zakat al-fitr) is required of him, and the fitra follows the maintenance, and the obligation of the subordinate upon a person is an indication of the obligation of the primary upon him. It is also possible that it is obligatory [upon the owner of] (17) the benefit. This is the view of the proponents of ra'y and Al-Istakhri (18), and it is the more correct view, God willing, because he possesses its benefit in perpetuity, so the maintenance is upon him, like a husband; and because its benefit is for him, so its detriment is upon him, like the owner of both together. This is confirmed by the fact that obligating maintenance on one who has no benefit from it is pure harm. Thus, the meaning of the bequest becomes: "I have bequeathed to you the benefit of my slave, and left the detriment of it upon my heirs." If he bequeathed its benefit to one person and its physical entity to another, the meaning would be: "I have bequeathed to this one its benefit, and to this one its detriment." The Shari'a refutes this with the saying: "There shall be no harm and no reciprocation of harm" (19). For this reason, it has established that "the revenue is for the one who bears the liability," so that its detriment is upon the one who has its benefit. This differs from a leased slave, for his benefit is, in reality, for the lessor, because he takes the rent as compensation for his benefits. It is said: His maintenance is obligatory upon his earnings. This returns to the view of obligating it upon the owner of the benefit; for his earnings are among his benefits, so if they are spent on his maintenance, the benefit (20) bequeathed is diverted to maintenance, becoming as if some of his other property was spent on him.
Section: If the heirs free the slave, he is emancipated, and his benefit remains for the legatee, and he does not return to the emancipator for anything. If the owner of the benefit frees him, he is not emancipated; because emancipation pertains to the physical entity, which he does not own. If the owner of the benefit gifts his benefits to the slave and waives them, the heirs have the right to benefit
(16) Omitted from M. (17) Omitted from the original, B, and M. (18) Abu Sa'id al-Hasan ibn Ahmad ibn Yazid al-Istakhri al-Shafi'i, the judge of Qom and one of the eminent scholars of the school. He died in the year 323 AH in Baghdad. Tabaqat al-Shafi'iyya al-Kubra 3/230-253. (19) In the original and A: "idrar" (harming). It was previously cited in 4/140. (20) In A and M: "sarfa" (spent).