Vow of a person with obsessive compulsive disorder
3-8-2015 | IslamWeb
Question:
Does OCD (obsessive compulsive disorder) affect the ruling of the vow? In other words, if a person with OCD frequently takes vows, will his condition be taken into consideration concerning the ruling of the vow? What is the ruling on the money (such as the salary) that is vowed by a person if he breaks his vow and does not fulfill it? Is that money considered unlawful to consume by that person, or is he considered guilty of a great sin by not fulfilling the vow but the money is still lawful to consume? In other words, if the person offers expiation for breaking the vow and then consumed that money, will he be sinful for that?
Answer:
All perfect praise be to Allaah, the Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and messenger.
If the vow is affected by the OCD case, meaning that the person doubts whether he has taken the vow or not, then the doubted vow is of no effect because, according to the basic rule, the person is free from liability. However, if one is afflicted by OCD but is sure of having taken the vow, then he has to fulfill it as long as he is able to do so, even if he frequently takes vows.
If one vows to offer a specific item of money, such as the salary or the like, then he has to fulfill it, and he may not use the money that he vowed because it is no longer his property as it became the property of the beneficiary of the vow. This is so unless the vowed thing represents all his money. Some scholars said that in this case it suffices him to fulfill the vow by giving one third of his wealth. Other scholars viewed that he should fulfill his vow according to the way that he specified. Ibn Qudamah 
said in Al-Mughni: "The conclusion is that if one vowed to give his entire wealth in charity, it suffices him to give only one third thereof. This is the opinion of Az-Zuhri and Malik ... An-Nakha‘i, Al-Batti and Ash-Shafi‘i 
said: "He should give all his wealth in charity because the Prophet, sallallaahu ‘alayhi wa sallam, said: 'If one vows to do an act of obedience to Allaah Almighty, then he should perform it,' and because it is a vow of obedience like vowing to pray or observe fast, so he should fulfill it."
Moreover, if one vows to obey Allaah, the Exalted, then he should fulfill his vow. Expiation does not avail him except in case of an inability that is not expected to be eliminated. Nevertheless, if it is a vow of lajaj (i.e. anger) by which he wants to prevent himself from doing something or to urge himself to do something, then he is given the choice between fulfillment and expiation according to the preponderant opinion.
Allaah Knows best.