Why does the date of Easter change?
Armenian Christian Catholic Iraqis sing during a mass for Easter Sunday celebrations at Umm al-Nour Church on April 5, 2015 in Erbil, the capital of the Kurdish autonomous region in northern Iraq. (AFP/Safin Hamed)
The celebration follows a 40-day period of fasting and prayers called Lent. Its last week is called the Holy Week, containing Holy Thursday that represents the commemoration of Last Supper, the event when Jesus and his disciples are believed to have dined together for the last time before his crucifixion and Good Friday, also known in Egypt as Sad Friday, which marks the commemoration of the crucifixion and death of Jesus Christ.
Why is the date of Christmas fixed, while the date of Easter can change? Why do Eastern Orthodox churches celebrate Easter on a different day than Western churches? Ahram Online attempts to answer common questions.
Why does the date of Easter change, unlike the date of Christmas?
Christmas: Although the exact date of Jesus' birth was -- and remains -- unknown, within the first few centuries after his death, churches around the world agreed to celebrate the nativity of Jesus on 25 December (or 29 Kiahk in the Coptic calendar), most probably to replace the pagan feast celebrating the Roman winter.
Easter: According to the Holy Bible, the death, burial, and resurrection of Jesus happened after Passover, a Jewish festival marking the commemoration of their Exodus from Egypt after 400 years of slavery and their freedom under the leadership of Moses. As the Jewish calendar is based on lunar cycles, each feast is movable, with dates shifting from year to year. Accordingly, the date for Easter is movable.
Coptic Easter is calculated as the first Sunday after the Passover full moon, which occurs on or after the spring equinox, when daytime and night are of approximately equal duration. If the full moon falls on a Sunday, then Easter is the following Sunday. As the full moon doesn't fall on a fixed date, but occurs between 22 March and 4 April, the date for Easter is therefore also not fixed.
Why does the Orthodox church celebrate Easter on a different day than other churches?
The difference is the result of a change in calendars. While Western churches follow the Gregorian calendar, Orthodox churches continue to follow the older Julian calendar, named after Julius Caesar who introduced it in 46 BC, which in turn is in line with the ancient Coptic calendar. The Julian calendar is now 13 days behind the Gregorian calendar, as this difference increases by a day every 128 years.
But the Eastern Church also sets the date of Easter according to the actual equinox and astronomical full moon as observed along the meridian of Jerusalem, site of the Crucifixion and Resurrection. The Western Church however fixes the date of the spring equinox to 21 March, and does not consider the actual, astronomical full moon but the "ecclesiastical moon," which is based on tables created by the church.
Why then do both churches sometimes celebrate Easter on the same date?
Sometimes, both churches celebrate Easter on the same date, as happened in 2014.
According to the Western Gregorian calendar, the first ecclesiastical full moon after 21 March fell on 15 April, so the next Sunday, 20 April, was Easter.
In the Orthodox Julian calendar, the astronomical spring equinox was observed on 7 March, or 20 April according to the Gregorian calendar, with the first full moon after that on 2 April, or 15 April, so Easter fell on 7 April, or 20 April.
Why isn't there a shared date for Easter around the world?
Since 1920, there have been many attempts to set a fixed date for Easter around the world. In 1997, the World Council of Churches held a meeting in Syria towards setting a calculation rule to reach a common fixed date, but since no action has been taken.
Last month, Egypt's Pope Tawadros II called Pope Francis to discuss the matter.
Why is Sham El-Nasim being celebrated on the day after Easter?
Sham El-Nasim has been celebrated in Egypt since 2,700 BC.
The name "Sham El-Nasim" literally means "inhaling the breeze", and is derived from the Coptic language that, in turn, is derived from Ancient Egyptian. It was originally pronounced Tshom Ni Sime, with tshom meaning “gardens” and ni sime meaning “meadows.”
Linked to astronomy and nature, Sham El-Nasim denotes the beginning of the spring festival, when the sun is in the Aries zodiac marking the beginning of creation. The exact date is confirmed annually by sighting the sun in relation to the Great Pyramid.
When Christianity became widespread in Egypt in the fourth century, Christians were unable to celebrate Sham El-Nasim, as it usually fell in the 40-day period of fasting before Easter. As Lent is a period of prayer and penance for sins and not a period of joy, they decided to postpone it until after Lent.
But there is also another reason. According to Christian beliefs, darkness overcame the land during crucifixion, and flowers only bloomed after the resurrection of Jesus Christ. In accordance with that, Sham El-Nasim is celebrated after Easter.
By Sherry El Gergawi