and convey to Khālid ibn al-Walīd that he must on no account kill a child, a hired laborer, or a woman.

In sum, the root cause of the jurists’ disagreement is their difference over the legal rationale that makes killing lawful. Those who hold that the decisive cause is disbelief itself exempt none of the idolaters. Those who contend that the cause is the enemy’s capacity to fight—citing the prohibition of killing women although they are unbelievers—exclude from combat anyone unable to fight and anyone who does not take up arms, such as the farmer or the hired hand.

The prohibition of mutilation is soundly established. The Muslims concur that the enemy may be killed with conventional weapons, yet they disagreed about killing by fire. Some—among them ʿUmar (and this is also narrated from Mālik)—disliked burning the enemy or hurling fire at them, whereas Sufyān al-Thawrī considered it permissible. Others said: if the enemy themselves begin using fire, it is allowed; otherwise, it is not.

The source of their divergence is the apparent conflict between a general text and a specific one. The general text is the Almighty’s words:
“Then slay the polytheists wherever you find them” (al-Tawbah 9:5),
which exclude no particular mode of killing. The specific text is the authentic report that the Messenger of Allah—peace and blessings be upon him—said about a certain man:
“If you capture him, kill him, but do not burn him with fire, for none punishes with fire except the Lord of Fire.”

The great majority of jurists hold that it is lawful to bombard fortresses with catapults, whether or not women and children are inside, because it is related that “the Prophet—peace and blessings be upon him—set up a catapult against the people of Ṭā’if.” If, however, Muslim captives and children are inside the fortress, one group—al-Awzāʿī among them—said the bombardment must be withheld, whereas al-Layth deemed it permissible. Those who prohibited it relied on the verse,
“Had they been separated, We would surely have punished the disbelievers among them with a painful punishment” (al-Fatḥ 48:25),
while those who allowed it appear to have looked to overriding public interest (maṣlaḥah).

This, then, is the degree of harm that may be inflicted upon enemy lives. As for the harm that may lawfully be done to their property—buildings, animals, and vegetation—the jurists again differed. Mālik allowed cutting trees and fruit and demolishing inhabited structures, but he did not permit killing livestock or burning palm-trees. Al-Awzāʿī disliked cutting fruit-bearing trees and destroying inhabited buildings, whether a church or otherwise. Al-Shāfiʿī said that houses and trees may be burned if they serve as strongholds, but he disliked demolishing houses and cutting trees when they are not used as fortifications.

Their divergence here is rooted in the fact that Abu Bakr’s practice differed from that of the Prophet—peace and blessings be upon him. It is established that “the Prophet—peace and blessings be upon him—burned the palm-trees of Banū al-Naḍīr,” while it is likewise established that Abu Bakr said, “Do not cut down any tree and do not demolish any inhabited building.” Whoever judged that Abu Bakr’s instruction was issued only because of the particular circumstances