The Eastern Orthodox Liturgical Calendar describes and dictates the rhythm of the life of the Eastern Orthodox Church. Passages of Holy Scripture, saints and events for commemoration are associated with each date, as are many times special rules for fasting or feasting that correspond to the day of the week or time of year in relationship to the major feast days. There are two types of feasts in the Orthodox Church calendar: fixed and movable. Fixed feasts occur on the same calendar day every year, whereas movable feasts change each year. The moveable feasts are generally relative to Pascha, and so the cycle of moveable feasts is referred to as the Paschal cycle.
Fixed feasts
The following list of dates links only to fixed feasts of the Orthodox Church. These are the fixed dates; the particular day on which that date is observed differs depending upon whether one follows the Julian Calendar or the Revised Julian Calendar. All dates having to do with Pascha - the beginning of Great Lent, Ascension, Pentecost, etc. - are moveable feasts, and thus are not on this calendar. These important notes should be remembered in using the following calendar:
For the day in the modern Gregorian Calendar. on which churches following the Julian Calendar celebrate any fixed date's commemoration, the 13 days which were lapsed to correct the calendar to the seasons must again lapse, by adding the 13 days to the dates below. For example, Christmas Day on the Julian Calendar falls on January 7 of the modern Gregorian Calendar.
The number of days by which the Gregorian calendar differs from the Julian calendar is currently 13, but will increase to 14 on March 1, 2100. Over the course of future centuries, the difference will continue to increase, limitlessly.
For those churches which follow the Revised Julian Calendar the dates below correspond exactly to the dates on the Gregorian Calendar.
is, by far, the most important day in the ecclesiastical year, and all other days, in one way or another, are dependent upon it. Pascha falls on different calendar dates from year to year, calculated according to a strict set of rules. While the Fixed Cycle begins on September 1, the new Paschal Cycle begins on "Zaccheus Sunday" in the Slavic tradition or the "Sunday of the Canaanite Woman" in the Greek tradition, eleven Sundays before Pascha, and continues until the Zaccheus Sunday or Sunday of the Canaanite Woman of the following year. The Epistle and Gospel readings at the Divine Liturgy throughout the year are determined by the date of Pascha.
There are Twelve Great Feasts throughout the church year—not counting Pascha, which is above and beyond all other feast days. These are feasts which celebrate major historical events in the lives of Jesus Christ or the Theotokos. Of these, three are on the Paschal Cycle:
In addition to Great Lent, there are three other lesser lenten seasons in the church year:
Nativity Fast
Apostles' Fast
Dormition Fast
The season from the Sunday of the Publican and Pharisee through Holy Saturday is called Triodion, while the season from Pascha through Pentecost is called the Pentecostarion.
Printed calendars
Because of the complexity created by the intersection of the various cycles, a number of Orthodox institutions will print an annual calendar which contains rubrics for the services during that particular year. Simpler wall calendars will show the major commemoration of the day together with the appointed scripture readings.