Shouldn’t Easter be a fixed date on the calendar? Especially if Easter is meant to celebrate the day of Jesus’ resurrection, shouldn’t the date remain the same every year? So why does the date of Easter change every year?
The modern-day calendar used throughout the Western World was introduced by Pope Gregory XIII in AD 1582. It adapted and replaced the Julian calendar, which had been in use since the time of Julius Caesar.
The Gregorian calendar accounts for a typical 365-day year. Since an actual year is 365.2425 days long, the Gregorian calendar includes an additional day on leap years (every four years). Plus, it necessitates that leap year not be observed on years ending in “00” that are not divisible by four hundred. (Thus, while leap year was observed in 2000, it will not be observed in 2100.)
Easter, however, does not follow the Gregorian calendar. Instead, it follows a lunisolar calendar (much like the Hebrew calendar). According to the Council of Nicaea in the year 325, Easter is to be celebrated on the first Sunday following the first full moon following the vernal equinox in the Northern Hemisphere. As a result, the date varies from year to year.
Given this description from the Council of Nicaea, the earliest possible date for Easter is March 22. The last time Easter fell on that date was 1818, and it will not do so again until 2285. Conversely, the latest possible date for Easter is April 25. The last time Easter fell on that date was 1943, and it will not do so again until 2038.
To further complicate matters, the Eastern Orthodox Church (with a few exceptions) still adheres to the Julian calendar. The result is that the date of Easter can be different for the Eastern Church than for the Western Church. Plus, while the Resurrection is believed to have taken place during the Jewish Passover, the annual celebration of Passover may fall on yet another weekend.
Over the years there have been some who have promoted the idea of establishing a more predictable date for Easter. Some have suggested a specific date (which would mean Easter would fall on a different day of the week) while others have suggested a specific Sunday (such as the second Sunday of April). Such ideas have gained some traction, but have not yet led to any serious consideration.
Regardless of when it falls, Easter remains the central celebration of the Christian faith as well as a major cultural and commercial holiday. Just be sure to check your calendar in advance so you don’t miss it!