 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 Jesus December 25. The corresponding Western season of preparation for Christmas, which also has been called the Nativity Fast and Street. Martin's Lent, has taken the name of Advent. The Eastern Fast runs for 40 days instead of 4 Roman Rite or 6 weeks Ambrosian Rite and thematically focuses on proclamation and glorification of the incarnation of God, whereas the Western Advent focuses on the two calming for-advance of Jesus Christ, His birth and His second-coming whore. Papyrusia? 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, Greek Orthodox Patriarchate of Jerusalem, Russian Orthodox Church, Serbian Orthodox Church, Georgian Orthodox Church, Ukrainian Orthodox Church, Macedonian Orthodox Church, and Mount Athos 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 till dusk from 1 December until 25 December on the Gregorian calendar. Sometimes the fast is called Philip's Fast or the Philippian Fast as it traditionally begins on the day following the Feast of Street. Philip the Apostle November 14. Some Churches, such as the Melchite Greek Catholic Church, have abbreviated the Fast to start on December 10, following the Feast of the Conception by Saint and of the Most Holy Philtochus.