Why is easter on a different date each year, and how is the date calculated?
The statement “Easter is always celebrated on the Sunday immediately following the first full moon after the vernal (spring) equinox.” is not strictly true, at least it hasn’t been since 325 AD. In 325 AD the Council of Nicea (part of the Western Church) decided to simplify deciding on the date of Easter. It is actually the first Sunday after the Paschal Full Moon, which can vary up to two days from the date of the actual full moon (which can be from March 21 to April 18). The date of the Paschal Full Moon is worked out from historical tables not the actual moon cycles. Therefore Western Christianity Easter can fall any day between March 22 and April 25. Also, if you where wondering why in Western and Eastern Christianity Easter is on a different day… Western churches used the Gregorian Calendar to calculate the date of Easter and Eastern Orthodox churches used the Julian Calendar. Hope this helps.
