Christianity, Judaism and Islam all have periods of time when self-denial and fasting are encouraged. For Christians, this is Lent, for Jews, Yom Kippur and for Muslims, Ramadan, which began Saturday. (Masons, too, are taught to "subdue our passions.")
The following is a description of Ramadan from Holidays.net:
Observed by more than one billion Muslims around the world, Ramadan is a time for spiritual purification achieved through fasting, self-sacrifice and prayers.
Celebrated during the ninth month of Islamic calendar, the fast is observed each day from sunrise to sunset. Fasting during Ramadan is one of the five Pillars of Islam. The Islamic belief that requires that Muslims perform five central duties in order to strengthen their faith. While Islam has two major sects, the Sunnis and the Shiites, all Muslims aim to realize these five pillars in their lifetime.
Click here for an explanation of Lent and Yom Kippur.
If one looks, and not even that closely, there are so very many similarities among the world's religions. Tolerance should teach us to appreciate the similarities and respect the differences among the religions, and to give members of faiths different from our own the dignity that they, too, are acting in good faith - pun intended!