Book of Siyar (Military Expeditions)

During the lifetime of the Messenger of Allah ﷺ, jihad was a communal obligation (fard kifayah); some held that it was an individual duty (fard ‘ayn). After his demise, unbelievers fall into two situations. The first is when they remain in their own lands: here jihad remains a communal duty, and once a sufficient number undertake it the burden is lifted from everyone else.

Among the other acts counted as communal obligations are: establishing decisive proofs and resolving difficult religious questions; mastering the sacred sciences—Qur’anic exegesis, hadith, and substantive law—at a level adequate for judgment; enjoining right and forbidding wrong; keeping the Kaʿbah vibrant each year by visiting it; removing harm from Muslims, such as clothing the naked and feeding the hungry when zakah and the public treasury do not suffice; bearing and giving testimony; the trades and crafts that sustain livelihoods; and responding to the greeting of peace when it is addressed to a group. Initiating the greeting is recommended, but not toward someone relieving himself, one who is eating, or someone in a bath-house, and no reply is required from them.

Jihad is not obligatory upon a minor, an insane person, a woman, an invalid, one whose lameness is obvious, an amputee, a paralytic, a slave, or anyone who lacks the equipment of battle. Every excuse that removes the duty of Hajj likewise removes the duty of jihad—except fear of the road because of unbelievers; and, according to the sounder view, fear of Muslim highwaymen is treated the same.

A debtor whose payment is due may not travel for jihad or any other journey without his creditor’s permission; if the debt is deferred he may travel, though another opinion forbids him any journey that involves danger. It is likewise unlawful to leave for jihad without the permission of one’s Muslim parents. This requirement is waived for travel undertaken to acquire knowledge that is a personal obligation, and—on the stronger view—even when the knowledge sought fulfils a communal obligation. If his parents and creditor first grant permission and then withdraw it, he must return so long as he has not yet taken his place in the ranks; but once fighting has begun, the more authoritative view is that it is forbidden to withdraw.

The second situation arises when the enemy enters one of our towns. Its inhabitants must repel them by whatever means they can. If there is time to prepare for battle, doing what one can becomes compulsory even for the poor, children, debtors, and slaves—without anyone’s permission. Some have said that