Fast (Sax. faestan, to keep), abstinence from food, especially as a religious observance; appliedalso to the period of such abstinence. Fasting was practised in all the old religions known to history, with the single exception of that of Zoroaster. It appears to have been also in use among the semi-civilized and savage tribes in both hemispheres. The Mohammedans observe strictly the fast of the month of Ramadan, abstaining from all food daily from sunrise until sunset. On the Hebrews the law of Moses enjoined one annual fast on the day of atonement; others were observed by the nation in course of time in memory of great calamities. The modern Hebrews observe six fasts of obligation; the most fervent keep many more. The fast consists in abstaining from all food and drink from sunrise till nightfall, the fast of atonement alone from sunset until nightfall the next day. Both the eastern and western churches from the earliest times observed the Lenten fast of 40 days in memory of Christ's fasting. The Greek church enjoins fasts on all Wednesdays and Fridays, on the 40 days before Christmas, and the 40 days before Easter, the period extending from the week after Pentecost until June 29, and from Aug. 1 to Aug. 14, besides numerous other fasts as a preparation to ecclesiastical festivals; in all 130 fast days in the year.

There is a legal distinction made by both the Latin and eastern churches between "fasting," which implies the refraining from all food, and "abstinence," which is the refraining from flesh meat, eggs, milk, butter, and cheese. Thus, Roman Catholics abstain from flesh meat on all Fridays except Christmas day, and on the rogation days, or three days before Ascension Thursday. The fasts universally observed in the Catholic church are those of Lent, of the ember days, and of the vigils of Christmas, Pentecost, the Assumption (Aug. 15), and All Saints (Nov. 1). -Protestants generally admit the utility of fasting, while denying its necessity. They do not admit the legal distinction between fasting and abstinence. The English church and the Protestant Episcopal church of America maintain on their ecclesiastical calendar, under the name of fasts, both the "days of abstinence" and the "fast days" of the Catholic church. The Presbyterian church in the United States follows the doctrine of the Westminster Confession, that "solemn fastings" are "in their times and seasons" to be used in a holy and religious manner. The Methodist Episcopal church enjoins fasting or abstinence on the people, and advises weekly fasts to be kept by her clergy.

The New England Puritans, while rejecting ecclesiastical fasts, observed themselves "seasons of fasting and prayer," and admitted both the right and duty of the civil ruler to set apart days for such purpose. In. New England it is still customary for the governors of states to appoint in the spring a day of fasting, humiliation, and prayer," which is generally observed in the churches. During the civil war the president of the United States recommended by proclamation such days to be observed by the nation.