It is recommended to fulfil the vow at the first possible opportunity. If a person is able to do so but postpones it and then dies, the pilgrimage is carried out from his estate.

If he vows to perform Hajj in that very year and is capable, the vow becomes binding; if illness prevents him, he must perform it later, whereas if he is kept back by an enemy, no make-up is required according to the prevailing view.

The same rule applies when he vows a specific prayer or fast within a set time: if illness or an enemy prevents him, he must make it up.

If he vows to offer a sacrificial animal, he must take it to Mecca and distribute its meat to the people there. If he pledges charity to the inhabitants of a named town, he is obliged to give it to them. If he vows to fast in a town without naming which one, the place is not fixed; the same applies to a prayer—except when he specifies the Sacred Mosque, and, according to one opinion, likewise the Prophet’s Mosque and al-Aqsa.

I say: the stronger view is that the Prophet’s Mosque and al-Aqsa are specified in the same way as the Sacred Mosque; Allah knows best.

If he vows an unrestricted fast, one day suffices; if he vows “days,” three days are required. If he pledges unspecified charity, or a prayer, two rakʿahs are required, although another opinion suffices with one rakʿah. On the first opinion, standing in those rakʿahs is obligatory when one is able; on the second, it is not.

If the vow concerns manumission, the first opinion requires a slave who meets the conditions of an expiatory offering, while the second accepts any slave.

I say: the second opinion is stronger here; Allah knows best.

If he vows to free a defective non-Muslim slave, freeing a sound slave fulfils the vow; but if he designates a particular defective slave, that one must be freed.

If he vows to pray standing, it is not valid to pray sitting, unlike the reverse case. If he stipulates a lengthy recitation, a particular surah, or congregational prayer, he must fulfil it.

The sound position is that a vow becomes binding for every act of devotion that is not originally obligatory, such as visiting the sick, accompanying a funeral, or giving the greeting of peace.