Why Does Easter’s Date Always Change?

 

This upcoming weekend brings Easter for 2021, the one holiday wherein you have a legitimate reason to be waiting for the last minute to do your shopping for the simple reason that it has no fixed date. So, why is this?

As far as holidays go, they generally have a set date. Independence Day is always July 4 and Christmas is always December 25 (unless you’re Orthodox, then it’s January 7 for you). Another time fixing method goes for Thanksgiving, which is always the 4^th Thursday of November, meaning that, while its date changes year to year, it’s always at the end of the month. And then there’s Easter, which can float from late March to late April. So what gives?

Blame the Moon.

The formula for determining the date of Easter is as follows: Easter Sunday falls on the first Sunday after the first Full Moon after the Spring Equinox. Still, though, you may still be asking why the holiday doesn’t have a fixed date because, after all, Christ only rose from the dead on one day, which leads many to ask why we celebrate the anniversary of His rising different days every year.

Well, blame the Moon (and the historical record) again.

As hard as it is to believe today in a world where Christianity is the world’s largest religion, it was anything but 2000 years ago. Thanks to the lack of historical records, we do not know for certain the years (let alone the dates) when Jesus was born and died. The only concrete reference we have as to when Jesus died was that it is well documented that He was crucified while in Jerusalem to celebrate Passover, a Jewish holiday whose date is set by the lunar calendar.

In its first 3 centuries as an underground religion, there was no real central authority for Christians on matters of religion. Result: different churches celebrated Easter on different dates, most often either on Passover itself or the Sunday immediately after. It was not until the Roman Emperor Constantine became a Christian and made Christianity the official religion of the Roman Empire that there was uniformity on matters of religion. It was only then that Easter was fixed as the Sunday following Passover.

As for some trivia, the earliest Easter was in 1818, when the Full Moon fell on the Equinox (a Saturday), and Easter was the following Sunday, March 22. The next time this will happen: 2285. The latest Easter was in 1943, when the Full Moon was the day before the Spring Equinox, which meant that another full lunar cycle did not result in another Full Moon until Sunday, April 18, which led to an Easter on the latest possible date: April 25. This will next happen in 2038.

On top of all the date shifting, Orthodox churches use the old Julian Calendar for determining religious holidays, which means that Western and Eastern Easter often fall on different dates, as they do this year. The next time both Easters sill sync up: 2025. 

 

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