The Ancient Formula for Determining Easter: How a 1700-Year-Old Decision Still Affects Us Today


We’re going to tackle an intriguing question many of us have wondered about: why does Easter Sunday fall on a different date each year? It’s one of those things that can catch us off guard, especially for worship leaders planning our worship services (I’ll ask Alexa several times in late December and January “When is Easter?”)

First things first, it’s important to understand the significance of Easter for Christians. This special day is all about celebrating the resurrection of Jesus from the dead – a cornerstone event in our faith. But unlike Christmas, which falls on December 25th every year, Easter seems to be hopping around (pun intended) our calendar.

The reason behind this lies in history and tradition. Early Christians wanted to celebrate Easter around the time of the Jewish Passover since it was closely linked with Jesus’ crucifixion and resurrection. Interestingly, Passover doesn’t have a fixed date either because it depends on the Jewish lunar calendar.

To accommodate both traditions, church leaders came up with a formula during an important gathering called the First Council of Nicaea back in 325 AD. The goal was to bring unity among Christians worldwide. They decided that Easter should always fall on the first Sunday following the first full moon after March 21st (the vernal equinox).

Now you might be thinking: “Why don’t they just use our regular calendar?” Well, here’s where it gets interesting! Our standard calendar is called the Gregorian calendar (introduced by Pope Gregory XIII), which is based on solar cycles rather than lunar ones like its Jewish counterpart. Therefore, determining Easter based solely on solar dates would result in inconsistencies.

While having Easter Sunday change dates each year may seem strange at first glance, there’s actually an incredible historical connection between Christianity and Judaism at play here – reminding us how interconnected these two faiths truly are. As we approach this season dedicated to celebrating Jesus Christ’s resurrection, let’s cherish the opportunity to come together with our fellow believers.

Make sure to carve out some time this week for reflection and prayer, asking God to guide us through this special season. And while you’re at it, why not share this fascinating piece of trivia with your friends and family during your Easter gatherings?


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