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2734. If a person takes an oath to perform an act or refrain from one, such as taking an oath to fast or to stop smoking, then if he intentionally acts contrary to it, he will have to pay a kaff¡rah. That is, he will either have to free a slave, or satiate ten poor people, or clothe them. If he is unable to do any of these, he must fast for three consecutive days.

2735. The act of taking an oath must fulfill the following conditions:
1. The person taking the oath must be b¡ligh and sane, and should take the oath consciously and volitionally. Therefore, the act of taking an oath by a minor, an insane person, an intoxicated person, or a person who has been compelled is not valid. The same will apply if a person unconsciously takes an oath in a moment of anger. The oath taken by a bankrupt or feeble-minded person is not valid in the event that it necessitates the disposal of their property.
2. The act for which one takes an oath should not be a makruh or a forbidden act. Similarly, the act that one takes an oath to refrain from should not be an obligatory or recommended act. To claim the obligation of an act which is the subject of an oath to perform or refrain from a canonically neutral act which does not possess any worldly or religious benefit is problematic.
3. A person should take the oath by one of the names of the Lord that is exclusively reserved for His Holy Essence, such as God or Allah. Similarly, if a person takes an oath by a name that is also used to refer to someone other than God, but it is so frequently used to refer to God that whenever it is employed, the Holy Essence of the Lord is evoked in the mind, such as taking an oath by the name the Creator or the Sustainer, it too will be valid. In fact, if he takes an oath using a name that is used to refer to God and someone other than Him, but intends to refer to God, obligatory precaution dictates that he act according to that oath.
4. He should pronounce the oath verbally. Hence, if he writes it down or intends it in his heart, it will not be valid. However, if a person who is unable to speak takes an oath by hand signing, it will be valid.
5. He should be capable of fulfilling the oath. If he is able to perform it upon taking the oath, but is rendered incapable later on, his oath will be void from the moment he became incapable of fulfilling it. The same applies if fulfilling the oath, vow or pledge entails such hardship, that it is not possible to bear it.

2736. If a father prevents his son from taking an oath, or a husband prevents his wife from taking an oath, their oaths will not be valid.

2737. If a son takes an oath without the permission of his father, or a wife without the permission of her husband, the father or the husband can cancel their oath. In fact, the apparent precept is that their oath without the permission of the father or the husband is not valid.

2738. If a person fails to fulfill his oath owing to compulsion or forgetfulness, no kaff¡rah will be due on him. The same applies if a person is compelled to not fulfill his oath.
The oath by a person who suffers from uncertainty.

2739. A person who takes an oath that his words are true, then if his words are indeed true, the act of taking the oath is makruh. However, if his words are false, it is forbidden, and amounts to one of the major sins. However, if he takes a false oath to save himself or another Muslim from an oppressor, it is not problematic; rather, at times it becomes obligatory to do so. However, if he is able to express it ambiguously ({^ While taking the oath, he should intend it in such a manner, that it does not amount to a lie^})., the obligatory precaution is that he should do so. For example, if an oppressor wishes to torment an individual, and asks a person if he has seen the individual, and he had seen him an hour ago, he should say that I have not seen him, and he should intend that he had not seen him since five minutes ago.