Unlike feasts such as Christmas, Easter is a movable holiday -- here's why.
Easter is a movable feast — its date varies from one year to the next. This can be quite troublesome in terms of practicality, but it’s also an occasion to remind ourselves that Christian practices are rooted in Jewish tradition.
The day when Christian Easter stopped coinciding with the Jewish Passover
Before becoming a Christian holiday, Passover was an Old Testament feast that originally celebrated nature. In a nomadic culture, the year began in spring. People greeted the lambing season that ensured the future of the flock and the prosperity of the clan. In sedentary, rural societies, the year began in the fall, the beginning of the agricultural cycle, when people celebrated the first sheaves of wheat.
This was the feast of Unleavened Bread, initially distinct from the Passover. It serves as a background for the Book of Exodus, the great epic recounting the departure from Egypt and the crossing of the Red Sea. The 14th of Nisan (“the first month) became the national holiday. The Jewish calendar is a lunisolar calendar:corresponding to 12 months (29 or 30 days) of the lunar cycle, plus an extra month from time to time that readjusted the year to the solar cycle.
Christians followed the Julian calendar. Actually, under Julius Caesar, Rome switched from a 10-month year (355 days), which began in March, to our year of 12 months (365 days), starting on January 1. So Christian Easter did not coincide with Jewish Passover, all the more so because people did not commemorate the exact date of Resurrection, but the Sunday closest to it. The day that previously began the week became Sunday: dies dominicalis (the Lord’s Day).
Why doesn’t the date of Easter correspond in all the Christian Churches?
We must add to this another challenge: the date of Easter doesn’t coincide in all Christian Churches. The Julian calendar year was 11 minutes too long. By the Renaissance, the accumulated drift was no longer tolerable. Pope Gregory XIII took out 10 days from the calendar – thus St. Theresa of Avila died in the night of October 4 … or October 15, 1582! He also did away with some leap years that took place early in the century.
But the Orthodox world has not aligned itself with the Gregorian calendar. Still, everyone respects the same rule decreed at the Council of Nicaea: Easter is the Sunday following the 14th day of the spring lunar equinox (as in 2007, 2011 or in 2014), or up to four or five weeks later as in 2002 or this year.
Father Alain Bandelier