Easter
Easter is the central feast in the Christian liturgical year. According to the Canonical gospels, Jesus rose from the dead on the third day after his crucifixion. His resurrection is celebrated on Easter Day or Easter Sunday (also Resurrection Day or Resurrection Sunday). The chronology of his death and resurrection is variously interpreted to be between AD 26 and 36, traditionally 33.
Easter marks the end of Lent, a forty-day period of fasting, prayer, and penance. The last week of the Lent is called Holy Week, and it contains Good Friday, commemorating the crucifixion and death of Jesus. Easter is followed by a fifty-day period called Eastertide or the Easter Season, ending with Pentecost Sunday.
Easter is a moveable feast, meaning it is not fixed in relation to the civil calendar. The First Council of Nicaea (325) established the date of Easter as the first Sunday after the full moon (the Paschal Full Moon) following the northern hemisphere's vernal equinox. Ecclesiastically, the equinox is reckoned to be on March 21 (even though the equinox occurs, astronomically speaking, on March 20 in most years), and the "Full Moon" is not necessarily the astronomically correct date. The date of Easter therefore varies between March 22 and April 25. Eastern Christianity bases its calculations on the Julian Calendar whose March 21 corresponds, during the 21st century, to the 3rd of April in the Gregorian Calendar, in which calendar their celebration of Easter therefore varies between April 4 and May 8.
Easter is linked to the Jewish Passover by much of its symbolism, as well as by its position in the calendar. In many European languages, the words for "Easter" and "Passover" are etymologically related or homonymous. The term "Pascha", from the same root, is also used in English to refer to Easter.
Easter customs vary across the Christian world, but decorating Easter eggs is a common motif. In the Western world, customs such as egg hunting and the Easter Bunny extend from the domain of church, and often have a secular character.
Easter and the holidays that are related to it are moveable feasts, in that they do not fall on a fixed date in the Gregorian or Julian calendars (both of which follow the cycle of the sun and the seasons). Instead, the date for Easter is determined on a lunisolar calendar similar to the Hebrew calendar. The First Council of Nicaea (325) established the date of Easter as the first Sunday after the full moon (the Paschal Full Moon) following the northern hemisphere's vernal equinox. Ecclesiastically, the equinox is reckoned to be on March 21 (even though the equinox occurs, astronomically speaking, on March 20 in most years), and the "Full Moon" is not necessarily the astronomically correct date.
In Western Christianity, using the Gregorian calendar, Easter always falls on a Sunday between March 22 and April 25, inclusively. The following day, Easter Monday, is a legal holiday in many countries with predominantly Christian traditions.
Eastern Christianity bases its calculations on the Julian Calendar. Due to the 13 day difference between the calendars between 1900 and 2099, March 21 corresponds, during the 21st century, to the 3rd of April in the Gregorian Calendar. Easter therefore varies between April 4 and May 8 on the Gregorian calendar (The Julian calendar is no longer used as the civil calendar of the countries where Eastern Christian traditions predominate). Among the Oriental Orthodox some churches have changed from the Julian to the Gregorian calendar and the date for Easter as for other fixed and moveable feasts is the same as in the Western church.
The precise date of Easter has at times been a matter for contention. At the First Council of Nicaea in 325 it was decided that all Christian churches would celebrate Easter on the same day, which would be computed independently of any Jewish calculations to determine the date of Passover. It is however probable (though no contemporary account of the Council's decisions has survived) that no method of determining the date was specified by the Council. Epiphanius of Salamis wrote in the mid-4th century: :...the emperor...convened a council of 318 bishops...in the city of Nicea...They passed certain ecclesiastical canons at the council besides, and at the same time decreed in regard to the Passover that there must be one unanimous concord on the celebration of God's holy and supremely excellent day. For it was variously observed by people....
In the years following the council, the computational system that was worked out by the church of Alexandria came to be normative. It took a while for the Alexandrian rules to be adopted throughout Christian Europe, however. The Church of Rome continued to use an 84-year lunisolar calendar cycle from the late 3rd century until 457. It then switched to an adaptation by Victorius of the Alexandrian rules. This table was so inaccurate that the Alexandrian rules were adopted in their entirety in the following century. From this time, therefore, all disputes between Alexandria and Rome as to the correct date for Easter cease, as both churches were using identical tables.