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When Is Easter 2016? And Why Does It Change Every Year?

02/22/2016 12:15 EST | Updated 03/21/2016 10:59 EDT

For Christians around the world, Easter Sunday — the day honouring Jesus' resurrection — is one of the most important days of the year. But this sacred day is also considered a "moveable feast" and can fall between March 22 and April 25 of any given year.

This year, Easter Sunday falls on March 27, 2016.

You're probably wondering why such an important date would move so much, or even how the date is chosen every year.

The Easter schedule was actually originally tied to the celebration of Passover, which is tied to lunar cycles. Since Jesus and his apostles were Jewish, Christ's death was recorded as occurring after Passover. Easter is celebrated shortly after that.

But there's more to that story. In ancient times, Christians around the world celebrated Easter on different days — some celebrated the day after Passover, while others celebrated on the first Sunday following Passover.

It wasn't until 325 CE that the Council of Nicaea created a mathematical formula to standardize the celebration date. Since then, Easter Sunday has been celebrated on the first Sunday after the first full moon of the spring season. If the full moon falls on a Sunday, Easter is celebrated the week after. The Hebrew calendar, which is entirely different from the Gregorian one, no longer plays a role.

And while the drastic shift in dates used to mean the difference between wearing winter boots to church vs. fancy dress shoes (or even an indoor vs. outdoor meal), this winter has been so unpredictable, it's worthwhile to plan for anything.

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