When fasting, Muslims are required to abstain from food, beverages (including water), and sexual intercourse during daylight hours (from dawn to sunset).
Sawm is especially associated with Ramadan, the ninth month of the Islamic calendar. Muslims who are physically able and not otherwise exempt (e.g., while traveling or waging jihad) are required to fast from dawn to sunset for the entire month. Fasting during Ramadan is one of the Five Pillars of Islam.
The Qur’an discusses fasting in Surat al-Baqarah:
Qur’an 2:183-185—O ye who believe! Fasting is prescribed for you, even as it was prescribed for those before you, that ye may ward off (evil); (Fast) a certain number of days; and (for) him who is sick among you, or on a journey, (the same) number of other days; and for those who can afford it there is a ransom: the feeding of a man in need—but whoso doeth good of his own accord, it is better for him: and that ye fast is better for you if ye did but know. The month of Ramadan in which was revealed the Qur'an, a guidance for mankind, and clear proofs of the guidance, and the Criterion (of right and wrong). And whosoever of you is present, let him fast the month, and whosoever of you is sick or on a journey, (let him fast the same) number of other days. Allah desireth for you ease; He desireth not hardship for you; and (He desireth) that ye should complete the period, and that ye should magnify Allah for having guided you, and that peradventure ye may be thankful.
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