Why do we celebrate the Glorious Feast of Resurrection this year with the Jewish Passover?
Our church follows the Apakty formula which is a means of calculating the full moon following the vernal equinox, and the date of the slaying of the Passover lamb. We celebrate the holy feast of the Resurrection on the Sunday following these dates. These dates were observed by all churches in the world since the council of Nicea in 325 A.D. However, in the sixteenth century, Pope Gregory of Rome changed the Roman calendar establishing a different calculation for the feast of the Resurrection, a clear infraction against the canon of Nicene council, which had confirmed the Apakty calculation and had given the Patriarch of Alexandria the right to set the feast's date. Pope Gregory decided to set the date to be the Sunday following the full moon following the vernal equinox, not considering the Passover Lamb, or the canon of the council of Nicea, or the spirituality of the teachings of the holy apostles, which urge us not to celebrate at the same time as the Jews.
Recently, the Jews have changed their calendar to match the Gregorian calendar, while we are still following the Julian or Coptic calendar resulting in this coincidence of celebrations on the same week.
You can read more about 'The Date Of The Glorious Feast Of The Resurrection' @ http://www.suscopts.org/literature/literature.php?subaction=showfull&id=1084913586&archive=&start_from=&ucat=21&.