مسائل المنتخبه (Articles Of Islamic Acts) - الخوئي، السيد أبوالقاسم - الصفحة ٥٦٥ - Vow and Covenant

particular time, he can perform that act after that time has passed, and if he performs that act before thattime owing to forgetfulness, or helplessness. nothing is obligatory on him. Even then it is necessary for him not to perform that act again till the appointed time, and if heperforms that act again before that time without an excuse, he must make atonement for it .
٢٦٦٥. If a person makes a vow to abandon an act but does not specify any time for it, and performs that act owing to forgetfulness, helplessness or negligence. it isnot obligatory for him to make atonement, but if he performs that act again at any time voluntarily. he must make atonement for it.
٢٦٦٦. If a person makes a vow that he/she will observe fast every week on a particular day e.g. on Friday, and Eidul Fitr or Eidul Azha falls on one of the Fridaysor an excuse like journey (or menses in the case of women) appears for him/her on a Friday he/she should not observe fast on that day but observe its qaza.
٢٦٦٧. If a person makes a vow that he will give a specific amount as alms, but dies before giving alms, it is not necessary that that amount should be given as almsfrom out d his property. It is better that the adult heirs of the deceased should give that amount as alms on his behalf out of their own share.
٢٦٦٨. If a person makes a vow that he will give alms to a particular person he cannot give it to another pool and if that poor person dies he should, on the basisof precaution, give the alms to his heirs.
٢٦٦٩. If a person makes a vow that he will perform the ziyarat (homage) of one of the holy Imams for example of Abu Abdullah Imam Husayn (P) his going for theziyarat of another Imam is not sufficient, and ii he cannot perform the ziyarat of that particular Imam on account of some excuse nothing is obligatory on him.