Have you ever wondered why Easter can fall in either March or April, unlike Christmas which is always on December 25th? For example, last year Easter was on April 9th, while this year it falls on March 31st.

The reason behind the shifting date of Easter is quite interesting. Easter is celebrated on the first Sunday after the first full moon that occurs on or after the vernal equinox.

The vernal equinox marks the first day of spring, typically falling on March 20th (this year, it was on March 19th). And of course, we all know what a full moon is.

Traditionally, Jesus' resurrection is associated with the Jewish Passover, which is celebrated on the first full moon after the vernal equinox.

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Some Christians initially celebrated Easter on Passover, while others waited until the following Sunday, as it was the day of the Resurrection. However, in 325 A.D. at the Council of Nicaea, Emperor Constantine wanted to unify the celebration of Easter on a specific date. It was then agreed that Easter would be observed on the first Sunday following the full moon.

Interestingly, while Christmas remains fixed on December 25th, the date of Easter influences the timing of several other Christian holidays throughout the year.

Easter determines the dates for Palm Sunday (March 24th this year), Good Friday (March 29th this year), Ascension Day (May 9th this year), and Pentecost (May 19th this year).

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