For the Western Churches that trace their lineage back through the Roman Catholic Church, today (10 April 2022) is Palm Sunday and the beginning of Holy Week. But for roughly 30% of the Christian World, Palm Sunday isn’t until next week (17 April). Why is a fascinating story that involves astronomy and geophysics, politics, and theology. Here’s a few notes for those who are curious …
At the time of Christ, the calendar in use was the Julian Calendar. Julius Caesar himself ordered it into use in 45 B.C to clean up a number of issues surrounding the old Roman calendar. His new calendar was designed with the help of Greek astronomers (who were among the best of the time) and by any measure it was a big advance, more closely matching the actual length of the time it takes the Earth to go around the Sun, which is 365.24219 days. The Julian Calendar is pretty close to that, 365.25 days. It did that by having a year that is 365 days for most years, but inserting an extra day in the month of February every four years. The problem is that over time, even that .00781 of a day adds up, so the calendar “drifts” by about one day every 128 years. They were aware of the problem but figured they could fix it later, Of course, like many problems politicians say will get fixed later, later never came, possibly due to stabby senators …
By the 1500’s that drift had added up to nearly 10 days, causing the calendar to be out of sync with the seasons and causing problems with the calculation of the date of Easter. So Pope Gregory XIII ordered a new calendar developed. It’s not really that different from the Julian Calendar, but tweaks things by making the average length of the year 365.2425 days (only .00031 days off, or one day of drift every 3225 years). It does this by dropping the leap year sometimes:
Every year that is exactly divisible by four is a leap year, except for years that are exactly divisible by 100, but these centurial years are leap years if they are exactly divisible by 400. For example, the years 1700, 1800, and 1900 are not leap years, but the years 1600 and 2000 are.
– US Naval Observatory FAQ.
In the Catholic world, the Gregorian Calendar came in to use in 1582. But while Gregory XIII was still called Pontifex Maximus, he was no Pater Patriae or Imperator like Julius … and by then the Western World was fragmented. The Roman Catholic Church had split off from the Eastern Churches in the Great Schism of 1054, and the Protestant Revolutions of the 1400’s had caused a major fracturing of Western Christianity. Most Protestant countries rejected the new “Papist” calendar even though it was technically more accurate, and more in sync with the seasons. The Orthodox Churches simply ignored it as just another Papal heresy to add to the increasingly long list 😛 . However, over time, the Protestant countries created their own, so called “Improved Calendar” that just happened to be identical to the Gregorian Calendar, so under whatever name by the 1700’s most of the western world had adopted the Gregorian Calendar. In the early 1900’s, most nominally Orthodox countries had adopted a split system: a civil calendar based on the Gregorian calendar, but the religious calendar and thus the calculation of the dates of Nativity (Christmas) and Pascha (Easter) stayed on the Julian Calendar.
So the situation today is that the Western Churches (Catholics and Protestants) use the Gregorian Calendar to calculate Easter, and the Eastern Orthodox Churches (Greek, Russian, Ukrainian, Serbian, Macedonian, Antiochian, the Orthodox Church in America, and so forth) use the Julian Calendar to calculate Pascha (Easter).
Today there is a 13 day difference between the Julian and Gregorian Calendars. Because Pascha/Easter are calculated based on the first Sunday after the first full moon after the spring equinox (on 20/21 March), that means the dates sometimes fall on the same day, but in other years can be up to a month apart! In 2016 Easter was March 23rd on the Gregorian Calendar, but Pascha was on May 1st Gregorian (April 18th Julian). This year (2022) they are only a week apart.
Nobody really disagrees with the fact the Julian Calendar has drifted, and the Gregorian Calendar is more accurate. Why haven’t the Orthodox Churches updated the calendar? Worse, why have some (like Constantinople) switched for the daily calendar but not for calculating Pascha? A key reason it remains unsolved involves the way the Churches are governed and how councils that can decide that sort of thing are convened. The Orthodox Church suffered two major disruptions in the early 1900’s, the Communist takeover of Russia (which is the largest Orthodox Church in numbers), and the collapse of the Ottoman Empire and rise of the secular Turkish regime. The situation in Turkey has become even more complex, and the Orthodox Church there nearly destroyed by the increasingly oppressive Islamic forces under Erdogan. There have been some attempts at convening a council but some complex politics have gotten in the way such as the growing Schism between Istanbul (Constantinople) and Moscow, and interference in Church affairs by secular authorities. But that’s a long. complicated mess … but the bottom line is in the Orthodox world, where things move slowly anyway, the mechanisms to fix things like the calendar problem aren’t working.
So that’s a bit of history. To wrap up, here are “Leonid and Friends” doing a fantastic cover of Chicago’s classic, “Does anybody really know what time it is?” This group is amazing – the musicians are scattered across Russia and Ukraine, working together even during COVID and the ongoing conflicts. They also did a session with Arturo Sandoval doing a trumpet solo on “Street Player”. Well worth exploring …