As for those among the unbelievers who are incapable of fighting—such as a decrepit old man, a chronically ill person, or a monk or hermit who has withdrawn from society—the matter must be examined. If they support the combatants with their counsel and incite them to fight, it is permissible to kill them when they are overcome, and after being captured they are subject to the same ruling as combatants. But if they neither share their views nor incite them, it is not permissible to kill them. This is the ruling concerning killing.
As for those taken captive, they are women and children. They may not be killed, whether they are from the People of the Book or from a people without a revealed scripture, such as the materialists and idol worshippers. They are to be taken as enslaved captives and distributed among those entitled to the spoils. This is the apparent import of al-Khiraqi’s statement, for he said: “They may only be enslaved if they are from the People of the Book or are Magians. As for all others among the enemy, nothing is accepted from their adult men except Islam, the sword, or ransom.”
The apparent meaning of this is that minors—male and female—are not to be killed. It is possible, nevertheless, that women and children from peoples other than the People of the Book are not to be killed, while adult men are to be killed, just as the blood of noncombatants among the People of the Book must be spared, whereas that of their adult men need not be.
Among those who are enslaved, close blood relatives within the prohibited degrees—such as parents and children, and brothers and sisters—must not be separated. Enslaved captives may not be ransomed for money, nor may they be exchanged for Muslim captives held by their people.
This is the apparent meaning of Ahmad’s statement, as narrated by Bakr ibn Muhammad from his father, concerning a child taken captive: “May he be exchanged for ransom while he is with his parents and follows their religion?” He replied, “No. Even if he follows their religion, he is not to be exchanged while they are young, for it may be hoped that their parents will die while they are still young and they will become Muslims.” Thus, he explicitly prohibited this in the case of children.