Introduction

2658. If a person makes a vow that he will perform or abandon a normal act, the performing or abandoning of which has equal merits, his vow is not in order. But if performing it is better in some respect, and a person makes a vow keeping that merit in view, for example, if he makes a vow that he will eat a certain food so as to gain strength for worshipping Allah, his vow will be in order.
Also, if its renouncing is better in some respect, and the vow to renounce it is made with that intention, for example, if he finds smoking is harmful and makes a vow not to smoke, his vow is in order. However, at any time when he feels that smoking is not harmful for him, the vow will cancel by itself.

2659. If a person makes a vow, that he will offer his obligatory prayers at a place where offering does not inherently carry higher spiritual merits, for example, he makes a vow to offer his prayers in a certain room, his vow will be valid, only if, offering prayers there has some merit, like, being able to concentrate better due to solitude.

2660. If a person makes a vow to perform an act, he should perform it in strict accordance with his vow. If he makes a vow to give Sadaqa, or to fast on the first day of every month, or to offer prayers of the first of the month, if he performs these acts before that day or after, it will not suffice. Also, if he makes a vow that he will give Sadaqa when a patient recovers, but gives away before the recovery of the patient, it will not suffice.

2661. If a person makes a vow that he will fast, without specifying the time and the number of fasts, it will be sufficient if he observes one fast. And if he makes a vow that he will offer prayers, but does not specify its number and particulars, it will be sufficient if he offers a two rak'at prayers.
And if he makes a vow that he will give Sadaqa, not specifying its nature or quantity, and he gives something which can be deemed as Sadaqa, his vow will be fulfilled. And if he simply makes a vow that he will act to please Almighty Allah, his vow will be fulfilled if he offers one prayers, or observes one fast, or gives away something by way of Sadaqa.

2662. If a person makes a vow that he will observe fast on a particular day, he should observe fast on that very day; and if he does not observe fast on that day intentionally, he should, besides observing the qadha for that fast, also give Kaffarah for it. And the Kaffarah applicable in this case is the one prescribed for violation of the Oaths, as will be mentioned later. However, travelling for him on that day is permissible, and he will not fast.
Also, it is not obligatory upon him to make a niyyat for ten days so as to be able to fast. If a person who made the vow could not fast on the particular day because of being on a journey, illness, or in the case of a woman, being in the state of Haidh, or for any good excuse, then he will give only qadha of that fast, and there will be no Kaffarah.

2663. If a person, of his own choice and volition, violates his vow, he should give Kaffarah for it.

2664. If a person makes a vow to renounce an act for some specified time, he will be free to perform that act after that time has passed. But if he performs it before that time, due to forgetfulness, or helplessness, there is no liability on him. Even then, it will be necessary for him to refrain from that act for the remaining time, and if he repeats that act before it without any excuse, he must give Kaffarah for it.

2665. If a person makes a vow to renounce an act, without setting any time limit, and then performs that act because of forgetfulness, helplessness or carelessness, it is not obligatory for him to give a Kaffarah, but, after the first instance, if he repeats the act again at any time, voluntarily, he must give Kaffarah for it.

2666. If a person makes a vow that he/she will observe fast every week on a particular day, for example, on Friday, and if Eid ul Fitr or Eid ul Azha falls on one of the Fridays or an excuse like journey (or menses in the case of women) springs up for him/her, he/she should not observe fast on that day, but give its qadha.

2667. If a person makes a vow that he will give a specific amount as Sadaqa, and dies before having given it away, it is not necessary that that amount be deducted from his estate. It is better that the baligh heirs of the deceased give that amount as Sadaqa on his behalf, out of their own shares.