Nativity Fast

The Nativity Fast is a period of abstinence and penance practiced by the Eastern Orthodox, Oriental Orthodox, and Eastern Catholic Churches, in preparation for the Nativity of Christ, (December 25). The corresponding Western season of preparation for Christmas, which also has been called the Nativity Fast and St. Martin's Lent, has taken the name of Advent. The Eastern fast runs for 40 days instead of four (Roman rite) or six weeks (Ambrosian rite) and thematically focuses on proclamation and glorification of the Incarnation of God, whereas the Western Advent focuses on the two comings (or advents) of Jesus Christ: his birth and his Second Coming or Parousia.

The Byzantine fast is observed from November 15 to December 24, inclusively. These dates apply to those Orthodox Churches which use the Revised Julian calendar, which currently matches the Gregorian calendar. For those Eastern Orthodox Churches which still follow the Julian calendar (Churches of Russia, Georgia, Serbia, Ukraine, Macedonia, Mount Athos and Jerusalem), the Winter Lent does not begin until November 28 (Gregorian) which coincides with November 15 on the Julian calendar. The Ancient Church of the East fasts dawn til dusk from the 1st December until the 25th of December on the Gregorian calendar.

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