The Paschalion Question – Historical, Canonical, Mathematical and Astronomical Aspects

Den Ortodokse Kirkes Kalender

F. dia­kon Irakli har fået publi­ce­ret en dyb­de­gå­en­de arti­kel i  tids­skrif­tet Inter­na­tio­nal Jour­nal of Ort­ho­dox The­o­lo­gy, num­mer 8/1, 2017 med tit­len “Histo­ri­cal, Cano­ni­cal, Mat­he­ma­ti­cal and Astro­no­mi­cal Aspects of the Pas­cha­li­on Question”.

An arti­cle by f. dea­con Irakli with the tit­le of “Histo­ri­cal, Cano­ni­cal, Mat­he­ma­ti­cal and Astro­no­mi­cal Aspects of the Pas­cha­li­on Question” was recent­ly publis­hed in a a sci­en­ti­fic, peer-review and open access jour­nal – Inter­na­tio­nal Jour­nal of Ort­ho­dox The­o­lo­gy, issue 8/1, 2017.

Abstra­ct:
The­re are dif­fe­rent calen­dar systems in use among Ort­ho­dox Chur­ches wor­ldwi­de. Non-movab­le Ort­ho­dox Chri­sti­an feasts like Nati­vi­ty, Annun­ci­a­tion, Trans­fi­gu­ra­tion, and so on, are cele­bra­ted accor­ding to two dif­fe­rent — Juli­an and Revi­sed Juli­an — calen­dars. Howe­ver, when it comes to the question of the Easter date, most of the chur­ches with some excep­tion cele­bra­te the feast of the Resur­rection of our Lord Jesus Christ on the same Sun­day. Despi­te dif­fe­rent calen­dar systems, it is pre­ci­se­ly the Easter date deter­mi­na­tion question on whi­ch all calen­dar systems are based. Pre­sen­ted paper stu­di­es the Easter date (also known as Pas­chal) rela­ted question from histo­ri­cal, cano­ni­cal, mat­he­ma­ti­cal and astro­no­mi­cal points of view. Two exi­sting pas­chal systems — Ale­xan­dri­an and Gre­go­ri­an — are pre­sen­ted here. Accor­ding to the­se systems, the dates of the Easter for the peri­od of 2000 — 2050 are calcu­la­ted and com­pa­red with the astro­no­mi­cal dates defi­ned by the Chur­ch cano­ni­cal requi­re­ments for the Easter date deter­mi­na­tion. Obtai­ned results reve­al that the Ale­xan­dri­an met­hod used in most Ort­ho­dox chur­ches often devi­a­te from the astro­no­mi­cal rea­li­ty and cano­ni­cal rules, and its accu­ra­cy can rea­ch only 29% for the given peri­od of years. On the other hand, the accu­ra­cy of the Gre­go­ri­an met­hod used in the Catholic/Protestant wor­ld can be as high as 92%.