Orthodox Christian Holy Days
The Eastern (Orthodox) Christian Churches use the Julian Calendar, as opposed to the Gregorian Calendar in use by the Western Church. Since the actual solar year is approximately 11.25 minutes shorter than the Julian year, by the 16th century the Julian Calendar was 10 days behind the solar year. At present the Gregorian and Julian Calendars are 13 days out of phase.
For both churches, movable festivals such as Pentecost and Ascension are based on Easter or Pascha (Orthodox Easter), which are determined by the timing of the moon and March Equinox; consequently, their dates vary from year to year. Pascha may be celebrated up to five weeks later than Easter because of the difference in calendars.
Great Lent is the Lenten season in Eastern Orthodox Christianity. Also called the Great Fast, it is the church’s longest, strictest and most important time of fasting, leading up to Pascha (Orthodox Easter Sunday). Like its Western Christian counterpart, Great Lent lasts 40 days (but includes Sundays) and moves from year to year, based on the date of Pascha. The period begins seven weeks before Pascha on Clean Monday and goes through Lazarus Saturday, the day before Palm Sunday; fasting continues until the morning of Pascha.
Starting the week before Lent, believers avoid meat and other animal products; eggs and dairy are allowed. In the first five days of Lent, nothing is eaten from Monday morning through Wednesday evening. Only two full meals are taken on Wednesday and Friday. Throughout the rest of Lent, meat and animal products, fish, dairy products, wine and oil are mostly avoided, with wine and oil allowed on weekends. During Holy Week, the last meal before Pascha is ideally Thursday evening and may include wine and oil. Great and Holy Friday is the year’s strictest fast day and is encouraged even for those who have not kept a strict Lenten fast. The fast may end Saturday night or on Pascha.