(يَا أَيُّهَا الَّذِينَ آمَنُوا كُتِبَ عَلَيْكُمُ الصِّيَامُ كَمَا كُتِبَ عَلَى الَّذِينَ مِنْ قَبْلِكُمْ لَعَلَّكُمْ تَتَّقُونَ)
[Surat Al-Baqarah 183]
O you who have believed, decreed upon you is fasting as it was decreed upon those before you that you may become righteous -
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ALQURAN is holy book as way of life for Muslims there more of law must obey for Muslim in they live. Include worship fasting every month of Ramadhan. Fasting not only not eat or drink but abstinence from carnal desire and keep away from wrong attitude.
In Wikipedia fasting more definitions in religion Islam
..... "Muslims believe that fasting is more than abstaining from food and drink. Fasting also includes abstaining from any falsehood in speech and action, abstaining from any ignorant and indecent speech, and from arguing, fighting, and having lustful thoughts. Therefore, fasting strengthens control of impulses and helps develop good behavior. During the sacred month of Ramadan, believers strive to purify body and soul and increase their taqwa (good deeds and God-consciousness). This purification of body and soul harmonizes the inner and outer spheres of an individual. Muslims aim to improve their body by reducing food intake and maintaining a healthier lifestyle. Overindulgence in food is discouraged and eating only enough to silence the pain of hunger is encouraged. Muslims believe they should be active, tending to all their commitments and never falling short of any duty. On a moral level, believers strive to attain the most virtuous characteristics and apply them to their daily situations. They try to show compassion, generosity and mercy to others, exercise patience, and control their anger. In essence, Muslims are trying to improve what they believe to be good moral character and habits.
Fasting is obligatory for every Muslim one month in the year, during Ramadhan. Each day, the fast begins at sun-rise and ends at sunset. During this time Muslims are asked to remember those who are less fortunate than themselves as well it bringing them closer to God. This also helps to give the digestive system a break. Non obligatory fasts are two days a week as well as the middle of the month, as recommended by the Prophet Muhammad.
Although fasting at Ramadan is fard (obligatory), exceptions are made for persons in particular circumstances:
Prepubescent children; though some parents will encourage their children to fast earlier for shorter periods, so the children get used to fasting.
Unconditional vomiting because the food leaves through an unintentional part of the gut.
Serious illness; the days lost to illness will have to be made up after recovery.
If one is traveling but one must make up any days missed upon arriving at one's destination.
A woman during her menstrual period; although she must count the days she missed and make them up later.
A woman till forty days after giving birth to child or miscarriage. But she must count the day she missed in Ramadan or they should donate the amount of a normal person's diet for each day missed to the poor or needy.
A woman who is pregnant or breast feeding. But she must count the day she missed in Ramadan or they should donate the amount of a normal person's diet for each day missed to the poor or needy.
An ill person or old person who is not physically able to fast. They should donate the amount of a normal person's diet for each day missed if they are financially capable.
A mentally ill person.
For elders who will not be able to fast, a lunch meal (or an equivalent amount of money) is to be donated to the poor or needy for each day of missed fasting.
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Fasting is forbidden on these days
Eid al-Fitr (1st Shawwal)
Tashriq (11th, 12th, 13th Dhulhijjah) in accordance with Sunni Islam.
Eid Al Adha (10th of Dhu al-Hijjah in the Hijri (Islamic calendar)). (Not necessarily the belief of all sects and schools of thought within the body of Shia Islam as various Shi'ite sects have opposing views."...
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