Every year the date of Easter varies, but have you ever wondered why it can’t be on the same date each year?
Easter is known as a moveable feast a Christian feast or festival that does not occur on the same date. Some feast days such of those of saints are fixed but Easter is not.
So how is the date worked out and who or what decides it.
The first council of Christian bishops got together with the Roman Emperor Constantine 1 in 325AD in Nicea. The meeting was to make an agreement on the date of Easter.
They decided that Easter Sunday, The anniversary of Christ’s resurrection would fall on the first Sunday which followed the paschal moon. Which means the next full moon after the spring equinox.
Some of the reason for a flexible date is that Easter must always occur on a Sunday because that was the day of Christ’s resurrection.
Easter Sunday falls on the first Sunday after the full moon date which based on mathematical calculations it falls on or after March 21st. In the years that the Paschal full moon dates do not coincide with the astronomical dates of these dates confusion can occur.
In 2019 the March Equinox in the Western Hemisphere happened on Wednesday, March 20th and the first full moon in Spring was March 21st. If the church followed the timing of these events Easter would have been on March 24th the Sunday after the full moon on March 21st.
The full moon date in March which is specified by the church’s lunar calendar, which is also called the full moon, was on March 20th, 2019. And it is one day before the ecclesiastical date of the March equinox March 21st. Because of this, the Easter date for 2019 is based on the next ecclesiastical Full Moon which is on April 18th and is why Easter 2019 fall on April 21st.
The Paschal Full Moon falls on a recurring sequence of 19 dates between March 21st t-April18th. Because Easter is always on the Sunday following the Paschal Full Moon it can fall on any date between March 22nd-April 25th.
Proposed reform to allow Easter date to be fixed.
In 1928 in the UK the Easter Act 1928 was established to allow the Easter date to be fixed as the first Sunday after the second Saturday in April. But this law was not implemented, even though it remains on the UK Statute Law Database.