How is the day of Pascha determined?
Pascha is celebrated on the first Sunday following the first full moon after the vernal equinox; if that full moon falls on a Sunday, Pascha is observed the following Sunday. The First Ecumenical Council required all the Churches to celebrate Pascha on the same Sunday (Nicaea, 325; see Q070, Q071), and the rule was afterward fixed by the Alexandrian reckoning; this put an end to the ancient diversity, some churches of Asia, following the Apostle John, had kept the feast on the fourteenth day of the moon with the Jewish Passover, whatever the day of the week (the “Quartodecimans”), while most kept it on the following Sunday, by binding Pascha forever to the Lord’s Day, the day of the resurrection itself (Mat 28:1). The Council’s twofold intent governs the rule: that all Christians should celebrate the feast of feasts together, on one day, and that this day should be reckoned independently of the Jewish computation, for the Passover of the Law was the shadow, and “Christ, our Passover, has been sacrificed” (1Co 5:7; cf. Col 2:16–17; see Q029, Q328): the Church does not wait upon the calendar of a covenant that has been fulfilled, but the sequence of the saving events themselves, the Lord crucified at the Passover season and risen on the first day, is honored in her reckoning. In accordance with the Byzantine interpretation of Apostolic Canon 7, Pascha is never celebrated before or together with the Jewish Passover, a rule that the Paschalion of the Church has always kept (Russian Catechism, vol. 2, 182). The elements of the calculation (the equinox and the full moon) are determined not by direct astronomical observation but by the tables and calendar in use at the time of the Council, the Julian, which most Orthodox Churches retain for this purpose to this day; and since the Julian reckoning of the equinox now falls thirteen days later than the astronomical one, the Orthodox Pascha coincides with the Western Easter in some years and falls one, four, or five weeks later in others.
The dating of the feasts, above all Pascha according to a common calendar has been a difficult question in every age: between East and West, whose different reckonings were already noted with mutual tolerance by St Irenaeus in the second century, when he reminded Pope Victor, in the dispute over the Quartodeciman churches, that “the disagreement in the fast confirms our agreement in the faith” (in Eusebius, Ecclesiastical History, V.24); and among the Orthodox themselves, especially since the calendar reforms of the twentieth century, disagreements which have at times been pushed as far as schism. Against this, the warning of St John Chrysostom stands as valid now as then: “even if the Church were mistaken, exactness in the observance of times would not be as important as the offense caused by this division and schism” (St John Chrysostom, Against the Judaizers III; see Q011, Q017).
The principle beneath his words is the Council’s own: the precise date is a matter of order and unity, not of dogma, and the very purpose of the Nicene rule was concord, so that to shatter the Church’s communion over the instrument of her concord is to destroy the end for the sake of the means. Christians should therefore keep the reckoning appointed by their bishops and the Church, pray and labor for the day when all who confess the risen Lord may again proclaim “Christ is risen!” on one and the same morning, and remember, meanwhile, that the feast is not the arithmetic but the Resurrection, “for as often as you eat this bread and drink this cup, you proclaim the Lord’s death until he comes” (1Co 11:26; see Q210, Q343), and on that Day, the eternal Pascha, there will be no calendars at all (Rev 21:23–25; see Q144, Q539).
