Fasting is one of the Five Pillars of Islam. Fasting is a far’d (obligatory) for adult Muslims, except those who are suffering from an illness, travelling, are elderly, pregnant, breastfeeding, diabetic, chronically ill or going through menstrual bleeding.
Narrated Ibn ‘Umar: Allah’s Messenger (ﷺ) said:
Islam is based on (the following) five (principles): 1. To testify that none has the right to be worshipped but Allah and Muhammad is Allah’s Messenger (pbuh). 2. To offer the (compulsory congregational) prayers dutifully and perfectly. 3. To pay Zakat (i.e. obligatory charity). 4. To perform Hajj. (i.e. Pilgrimage to Mecca). 5. To observe fast during the month of Ramadan.
– Sahih Al-Bukhari, Vol. 1, Book 2, Hadith 8.
According to the Qur’an, fasting was also obligatory for prior nations, and is a way to attain taqwa, fear of God. God proclaimed to Muhammad (pbuh) that fasting for His sake was not a new innovation in monotheism, but rather an obligation practiced by those truly devoted to the oneness of God.
“O you who have believed, decreed upon you is fasting as it was decreed upon those before you that you may become righteous.” – Qur’an 2:183
Fasting is a way of experiencing hunger and developing sympathy for the less fortunate, and learning thankfulness and appreciation for all of Allah’s bounties. Muslims think of it as a kind of tune-up for their physical and spiritual lives.
The term “to fast” literary means “to refrain” i.e. absolute abstention and self-restraint. According to Islamic legislation fasting means abstention from drinking, eating, sexual intercourse and any form of bad deeds or evil actions such as stealing, lying, abusing, quarreling, gossiping etc.
So, a Muslim must fast in the month of Ramadan in order to achieve great reward and to become successful in the hereafter.
“O you who believe! Keep your duty to Allah and fear Him, and speak (always) the truth. He will direct you to do righteous good deeds and will forgive you your sins. And whosoever obeys Allah and His Messenger (SAW) he has indeed achieved a great achievement (i.e. he will be saved from the Hell-fire and made to enter Paradise).” – Qur’an 33:70-71