Al-Ḥasan ibn Muḥammad al-Tamīmī reports that this was the unanimous position of the Companions.

The root of the jurists’ disagreement lies in the apparent tension between the Qur’anic verses relevant to the matter, the Prophet’s actions, and the seeming conflict between the outward sense of revelation and his practice—peace and blessings be upon him.

The plain wording of the Almighty’s statement,

“So when you encounter those who disbelieve, strike their necks …” (Muḥammad 47:4),

indicates that, once prisoners are taken, the imām has only two choices: to show them favor and release them or to accept ransom. Likewise, His words,

“It is not for a prophet to have captives until he has thoroughly subdued the land …” (al-Anfāl 8:67),

and the occasion of revelation—namely the captives of Badr—suggest that killing is preferable to enslavement.

Yet the Prophet himself—peace and blessings be upon him—executed prisoners on more than one occasion, while at other times he granted them amnesty and enslaved the women. Abū ʿUbayd relates that he never enslaved free Arab men, even though the Companions after him unanimously agreed to enslave male and female People of the Book.

Thus, whoever deems the verse about prisoners to have abrogated the Prophet’s earlier practice maintains that a captive may not be put to death. On the other hand, whoever holds that the verse neither mentions the killing of prisoners nor intends to confine their rulings to what it states—given that the Prophet actually did execute captives, which constitutes an additional ruling and removes the reproach incurred by sparing the Badr prisoners—rules that executing a prisoner is permissible.

Execution, however, is only allowed if no pledge of safety has previously been granted; on this point there is no dispute among Muslims. Their difference concerns who may grant such safety and who may not. All agree that the imām may do so. The majority of scholars also allow a free Muslim man to extend safe-conduct, except Ibn al-Mājishūn, who conditions it on the imām’s approval.

They differ over the pledge of a slave and that of a woman: the majority consider both valid, whereas Ibn al-Mājishūn and Sahnūn hold that a woman’s pledge depends on the imām’s permission. Abū Ḥanīfah contends that a slave’s guarantee is invalid unless the slave himself has fought.

The basis of their disagreement is the clash between a general text and an analogical argument. The general text is the Prophet’s saying—peace and blessings be upon him:

“The blood of the Muslims is of equal worth; the least of them may grant protection on their behalf; and they stand united against all others.”

By its universality this ḥadīth validates the safe-conduct offered by a slave. The opposing analogy argues that a valid pledge of safety requires full legal capacity, while slavery entails a deficiency. Therefore that deficiency should negate the slave’s authority to give such a pledge, just as it negates many other legal rulings, thereby restricting the general text by means of this analogy.