According to the 4th pillar of islam, during the holy month of ramadan muslims must

In the month of Ramadan, Muslims must fast. Fasting is abstaining, totally or partially from eating and drinking for a while. Fasting usually is done for religious, moral or health reasons.

Explanation:

The Muslim religion is based on 5 basic principles, these are:

- The profession of faith, "There is no God except God and Muhammad is his prophet"

- The ritual prayer, five times a day, at certain times and in the direction of Mecca

- Alms, which is of two types: spontaneous, and the regulated or obligatory called tithing

- Fasting during the month of Ramadan. Ramadan is the ninth month of the Muslim calendar and is the month in which the revelation of the Koran began. From sunrise to sunset, followers of Islam should refrain from eating, drinking, smoking and having sex.

- The pilgrimage to Mecca. At least once in a lifetime, all Muslims with sufficient means have to make a pilgrimage to Mecca and The Great Mosque, and before the Ka’ba say: “Here I am at your service, Oh Allah”.

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