fasting, partial or temporary abstinence from food, a widely used form of asceticism. Among the stricter Jews the principal fast is the Day of Atonement, or Yom Kippur; in Islam the faithful fast all the daytime hours of the month of Ramadan. Fasting is general in Christianity. The most widely observed fasts are Lent and Advent. Both of these are preliminary to seasons of great rejoicing, and traditionally the vigils of several feasts were also kept as fasts, e.g. (in the West), those of Christmas, Easter, Whitsunday, the Assumption, and All Saints. Ember days were also fasts in the West. Protestants have generally abandoned fasting, but in New England an annual Fast Day was proclaimed (in Massachusetts until the 20th cent.). In the late 1990s there was renewed interest among evangelical Christians in the United States in fasting and prayer as a means of spiritual revival. The Roman Catholic Church differentiates between fasting (eating only one full meal and little else in a day) and abstinence (eating no flesh meat). In 1966, Pope Paul VI issued Poenitemini, an apostolic constitution reorganizing the discipline of the Catholic Church. Ash Wednesday and Good Friday are now the only required days of fast. The observance of Fridays as days of abstinence is now urged rather than, as formerly, made a matter of obligation. Roman Catholics are asked to abstain from food and drink for one hour prior to receiving communion. Fasting and hunger strikes have also been used by various political and social activists to bring attention to the causes they support.

Abstaining from food, usually for religious or ethical reasons. In ancient religions it was used to prepare worshipers or priests to approach deities, to pursue a vision, to demonstrate penance for sins, or to assuage an angered deity. All the major world religions include fasting among their practices. Judaism has several fast days, notably Yom Kippur. For Christians Lent is set aside as a 40-day period of penitence before Easter, including the traditional fast days of Ash Wednesday and Good Friday. In Islam the month of Ramadan is observed as a period of total abstention from food from dawn to dusk. Fasting to make a political protest is often referred to as a hunger strike; hunger strikes have been employed by, among others, 19th-century female suffragists, Mohandas K. Gandhi, and late-20th-century Irish nationalists. Moderate fasting is also sometimes practiced for its claimed health benefits.

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