What are the differences between the Old Calendar and the New?
The calendar in use when Christ was living was the Roman calendar, devised by Emperor Julius Caesar in the year 46 B.C. For this reason, it is known as the Julian Calendar. It was an improvement over the pre-existing calendar since the length of the year (one revolution of the earth around the sun) was more accurately calculated. But it was not fully accurate. By the first Ecumenical Council in 325 A.D., it was already four years out of synchronization. Thus, the Vernal equinox (the date in Spring when day and night are exactly equal in length) had to be moved from March 25 to March 21.
As the years went by, the difference increased. In 1582, Pope Gregory the 13th reformed the Julian Calendar. He omitted ten days from it in that year to correct the accumulated error and altered the leap year rule so that it wouldn't happen again. The "New Calendar," as a result, is known as the Gregorian Calendar. Those Orthodox churches which keep the Julian, or Old Calendar for the liturgical life are known as "Old Calendarist Churches." Most of these are the Slavic Orthodox Churches. However, by today there is a 13 day difference between the Julian and Gregorian calendars. For example, in the Old Calendar, Christmas Day, Dec. 25, falls thirteen days later than the Gregorian calendar. So Old Calendarist Orthodox celebrate Christmas on Dec. 25, according to the Julian Calendar, but it falls on Jan. 6, according to the new calendar now in use. In the Orthodox world the difference was noted as early as 1382 by astronomers of the Byzantine Emperor and suggestions were made for its correction. However, for pastoral reasons the corrected calendar was not accepted by any Orthodox. In 1924 the Ecumenical Patriarchate and the Church of Greece made the change, followed by several other Orthodox churches. Today, the Antiochian Church in this country follows the New Calendar as do many of the other jurisdictions, together with the Greek Orthodox Archdiocese. The "Orthodox Church in America" (former "Russian Metropolia") has decided to encourage their parishes to use the New Calendar. Other jurisdictions of Russian origin still retain the Julian Calendar, but the general movement among the Orthodox is toward the acceptance of the New Calendar for the liturgical life of the church.
