Who is required to fast?
Fasting during Ramadan is obligatory for every adult, sane, resident, capable Muslim who is free of any impediments. As for the infidel, fasting is not obligatory for him and it is not valid to do so. Because he is not worthy of worship, and when he converts to Islam, he is obligated to fast from the time of his conversion to Islam, and he does not make up for the past. This is indicated by the Almighty’s saying: Say to those who disbelieve, if they desist, what has come before will be forgiven them. ﴾ [الأنفال: 38]As for the child, he does not have to fast until the pen is removed from him until he reaches puberty. He reaches puberty by one of three things:
A- Ejaculation of semen during a wet dream or otherwise.
for- Pubic hair plant.
C- Attaining fifteen years of age.
The female has more menstruation than the male; When you are informed of it, or one of the previous three things.
As for the insane person, he is not obliged to fast to remove the pen from him, and if the person goes mad sometimes and wakes up at other times, he is obligated to fast whenever he regains consciousness, and he is not obliged to make up for what he went mad in.
As for the traveler, he is not obligated to fast. Rather, he has the choice between breaking the fast and fasting, and it is better for him to do what is easier for him. God Almighty says: And whoever is sick or on a journey, then a number of other days. ﴾ [البقرة: 185].
As for the incapable – who is unable to fast due to illness or old age – he is not obligated to fast, but rather makes it up after Ramadan, and the elderly feed one poor person for each day.
As for someone who has an impediment to fasting, he is not obliged to fast, rather he must break his fast, and the impediment is such as menstruation and postpartum.[1].
Ibn Rushd said: (As for the one who is obligated to do so without having a choice, he is an adult, sane, present, and sound, if he does not have a characteristic that prevents fasting, which is menstruation for women. There is no dispute over this, according to the Almighty’s saying:) So whoever of you witnesses the month, let him fast it. ﴾ [البقرة: 185])[2].
[1] The place for detailing the discussion about those who may break the fast is in the excuses that make it permissible to break the fast.
[2] Bidayat al-Mujtahid, vol. 1, p. 274, Bada’i al-Sana’i, vol. 2, p. 77, vol. 3, p. 176, Kashshaf al-Qina’, vol. 2, p. 308, and al-Sail al-Jarar by al-Shawkani, vol. 2, p. 111.