I want to ask you a question which makes me worried and disturb since last 2 years. As 2 years back my son aged 7 years fall seriously ill, I was there and looking at him, Doctors were pumping and breathing him artificially, being a father I was worried and at the moment I, promised Allaah to have fasting for one year if He gives my child a new life, and he gave (so thanks of him) since then I am worried about what to do, whether I should fast continuously for one year(without intervals or gap) or Can I complete number of days of one year (i.e. 360 or 365 days) with suitable gaps (while making promise I have not mention about it nor it was in my mind). Please help me and answer me as earliest as possible. I will be very grateful to you.
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 is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.
Whoever vows to obey Allaah and conditioned that vow upon the realization of something, then he/she must fulfil the vow upon the realization of such condition, as the Prophet said: "Whoever vows to obey Allaah has to obey Him." [Al-Bukhari] Therefore you have to fast for a whole year. However, the scholars differed in opinion whether or not it is a condition for a person to fast consecutively. Nonetheless, the most preponderant opinion is that whoever vows to fast a whole year without any specification and did not set any condition that he will fast consecutively, and this is your case as understood from the question, then he does not have to fast for a whole year consecutively. This is the view of the Hanafi, Maaliki and Shaafi'ee schools, and according to one of the two narrations of the Hanbali school.
Imaam An-Nawawi said: 'Whoever vows to fast a whole year and did not set any condition as to the manner of fasting, then it is not a condition for him to fast consecutively; he may fast 360 days or twelve lunar months, he can choose whichever option he wants, and that is accepted from him. Any month that he fasted from the beginning but then failed to fast any day or days due to a sound valid reason, then it is considered as he had fasted the whole month. If he had not fasted from the beginning but intended to fast a month, then he has to fast thirty days.'
Imaam Ibn Qudaamah said: 'He has to fast twelve lunar months if he so wishes, and he may also fast according to the number (of days) if he so wishes. But if he starts fasting from the middle of the month, then he has to fast thirty days.'
Finally, we draw your attention to the following two matters:
1) You have to break the fast on 'Eed days and the three days following 'Eed Al-Adh-Haa as the Prophet forbade us to fast these days.
2) You have to fast Ramadan making the intention of fasting Ramadan as it is not permissible to fast this month with the intention of fulfilling the vow, or to combine the intention of fasting Ramadan and the intention of fulfilling the vow at the same time.
Allaah knows best.
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