To a Muslim, fasting is not just refraining from eating and drinking but carries the added significance of worship, psychological comfort, morality and legislation. It is neither the irrational motionless Imsak of pre-Islamic Arabs nor the mere abstaining from eating and drinking, but is in fact the building of one's character, control over desires, and an inspiration towards social and scientific creativity.
Allah has commanded this sanctified duty and enjoined it on the Muslims, as He had enjoined it on the believing nations before. He assigned the blessed month, the month of Ramadhan, for every adult and healthy Muslim as a period of fasting.
This sacred ordinance was prescribed by Allah, the Exalted for all believers and revealed in the preceding month of Sha'ban, nearly a year and a half after the Hijrah.*
Gradually, the Almighty revealed numerous other verses about the month of Ramadhan and the rules of fasting. In the light of these divine injunctions,the Prophet expounded the merits of fasting, its significance, regulations, effects, benefits and great reward.
Hence, Fasting is one of the pillars of Islam, and a religious duty for all those who believe in Monotheism, and consequently whoever denies it is a disbeliever.
It is an apparent sign of obedience, submission and servitude to Allah, the Exalted. By fasting, a Muslim expresses his submission to Allah's command, his response to His will, and the control over his own desires and wishes, at the Almighty's behest. In Ramadhan a Muslim's abstaining from food, drink, sexual intercourse, etc. during the prescribed hours, is the very manifestation of the creatures' obedience to the Creator's Will.