Ruling 1707. Fasting on Eid al-Fiṭr[1] and Eid al-Aḍḥā[2] is unlawful. Furthermore, if one does not know whether it is the last day of Shaʿbān or the first day of the month of Ramadan and fasts with the intention of it being the first day of the month of Ramadan, it is unlawful.

Ruling 1708. If a recommended fast of a woman conflicts with her husband's conjugal rights, it is unlawful for her to keep it. Similarly, with regard to a fast that is obligatory but the day on which it must be kept has not been assigned – for example, a vow that [has been made to keep a fast, but the day of the fast] has not been assigned – if it conflicts with the conjugal rights of her husband, then based on obligatory precaution, the fast is invalid and it does not fulfil the vow. Based on obligatory precaution, the same applies if her husband forbids her to keep a recommended fast or an obligatory fast for which a day has not been assigned, even if it does not conflict with his rights. And the recommended precaution is that she should not keep a recommended fast without his consent.

Ruling 1709. If a recommended fast kept by a child is a source of annoyance for his father or mother due to their compassion for him, it is unlawful for the child to keep it.

Ruling 1710. If a child keeps a recommended fast without the consent of his father or mother and during the day his father or mother forbid him to continue keeping his fast, in the event that the child’s opposition may annoy the parent due to the parent’s compassion for his or her child, the child must break his fast.

Ruling 1711. Someone who knows fasting will not cause him significant harm – even though a doctor says it is harmful for him to fast – must fast. And someone who is certain or supposes that fasting will cause him significant harm – even though a doctor says it will not harm him – is not obliged to fast.

Ruling 1712. If a person is certain or confident that fasting will cause him significant harm or he deems this probable, and the probability creates fear in him, in the event that his deeming it probable would be considered by rational people to be reasonable, it is not obligatory for him to fast. In fact, if that harm would result in him dying or losing a limb, fasting is unlawful; otherwise, if he fasts with the intention of rajāʾ and afterwards he realises that it did not cause him any significant harm, his fast is valid.

Ruling 1713. If someone who believes that fasting does not harm him fasts and after maghrib he finds out that fasting has caused him significant harm, then based on obligatory precaution, he must make it up.

Ruling 1714. Apart from the fasts mentioned here, there are other unlawful fasts mentioned in more detailed books.

Ruling 1715. Fasting is disapproved on the Day of ʿĀshūrāʾ[3] and on the day that one doubts is the Day of ʿArafah[4] or Eid al-Aḍḥā.[5]