9th Month of the Muslim Calendar Based on a lunar calendar and therefore varies every year. The Holy Month of Ramadan is a time when Muslims fast during daylight hours to celebrate the time when Allah revealed the first verses of the Qu'ran, the holy book of Islam. It is a time for spiritual reflection, prayer, doing good deeds, charity, spending time with loved ones. It teaches self-discipline, self-restraint, generosity and understanding of those less fortunate.