Second: Obligatory fasting
This is the fasting that is obligatory for the Muslim; he is rewarded for performing it and punished if he abandons it. He is obliged to make up for it if it is invalidated or broken. In this fast, the intention before dawn is obligatory and performing it does not depend upon the permission of a husband to his wife.
There are numerous instances when fasting is obligatory:
A- Making up for the missed fasts
Allah The Almighty, Says (what means): {[Fasting for] a limited number of days. So whoever among you is ill or on a journey [during them] - then an equal number of days [are to be made up]} [Quran 2:184].
A person who suffers from an illness which makes fasting difficult, or which may exacerbate the illness or delay the cure, is allowed by Allah The Almighty not to fast. Similarly, a person who is travelling is exempted from fasting to avoid hardship. In order to achieve the benefit of fasting for every believer, Allah The Almighty ordered those who did not observe fast for some days in Ramadan to make up for them by fasting on other days when he recovers or when he returns from traveling.
If fasting is difficult, it is preferred to break the fast in such circumstances, as Allah The Exalted Says (what means): {Allah Intends for you ease and does not intend for you hardship} [Quran 2:185]. In addition, it was narrated on the authority of Anas, may Allah be pleased with him, that he said, "We used to travel with the Prophet and neither did the fasting people criticize those who were not fasting, nor did those who were not fasting criticize the fasting ones." [Al-Bukhari]
Moreover, a woman having menses or post partum bleeding is not to observe fasting; she should later make up for the same number of days she did not fast in Ramadan. She may seek days of short fasting periods rather than long ones or days of moderate weather instead of hot or cold days and the opposite is permissible.
The days may be continuous or separate. A person may delay making up for the fast even if he is able, however, it is better to hasten to it. This is supported by the Hadeeth in which ‘Aa’ishah, may Allah be pleased with her, says, "I used to have days of fasts from Ramadan to make up for, but I could not do it except during the month of Sha‘baan due to my duties towards the Messenger of Allah ." [Al-Bukhari]
If someone delayed fasting till Ramadan is over without a reason that prevents him, some scholars adopted the view that he should make up for this by fasting and feeding the needy for every day he did not make up for it till the advent of Ramadan. Nonetheless, Al-Bukhari rejected this opinion saying that Allah The Almighty did not mention feeding the needy, He, rather, Says (what means): {then an equal number of days [are to be made up]}
B- Fasting to fulfill a vow
A vow signifies an act of worship or charity or the like that a slave imposes upon himself voluntarily. Allah The Almighty Says (what means):
· {And if you see from among humanity anyone, say, 'Indeed, I have vowed to the Most Merciful abstention, so I will not speak today to [any] man.' "}[Quran 19:26]
· {And whatever you spend of expenditures or make of vows - indeed, Allah knows of it. And for the wrongdoers there are no helpers}[Quran 2:270]
· {[Mention, O Muhammad], when the wife of ‘Imraan said, "My Lord, indeed I have (vowed) pledged to You what is in my womb, consecrated [for Your service], so accept this from me. Indeed, You are the Hearing, the Knowing."} [Quran 3:35]
Allah The Exalted praises those who fulfill their vows in the verse in which He Says (what means): {They [are those who] fulfill [their] vows and fear a Day whose evil will be widespread} [Quran 76:7] There is no mention of praising those who make vows. Ibn ‘Umar, may Allah be pleased with him, narrated that the Prophet, , forbade vowing and said: "It (vowing) does not prevent anything, but it makes the miser spend (from his property)." [Al-Bukhari and Muslim]
This prohibition confirms and warns against neglecting the vow after making it. If this was intended to prohibit making vows, it would have annulled its content and relieved one of fulfilling it. This is why it was narrated on the authority of ’Aa’ishah, may Allah be pleased with her, that the Prophet, , said: "Whoever vows to obey Allah, should obey Him; and whoever made a vow that he will disobey Allah, should not disobey Him." [Al-Bukhari]
It was narrated on the authority of ‘Imraan ibn Husayn, may Allah be pleased with him, that he said that the Prophet, , said: “The best of you (people) are my generation, then those who will follow them, and then those who will follow them. Then will come people who will make vows but will not fulfill them; and they will be dishonest and will not be trustworthy, and they will be witnesses but will not be asked to give their witness, and fatness will appear among them." [Al-Bukhari and Muslim]
If a slave dies and he had vowed to fast, his guardian should fast on his behalf. ‘Aa’ishah, may Allah be pleased with her, said: "Whoever died and he ought to have fasted, then his guardian must fast on his behalf." [Al-Bukhari]