The First Ecumenical Council, the meeting of Christian bishops that was held in 325 in Nicaea (today Ýznik, Turkey), laid the groundwork for reaching consensus within the Church through an assembly representing all of Christendom. This event marked a key moment in the history of Christianity, 17 centuries ago this year, in which, among other decisions, the way of calculating the date of Easter was established. However, over the centuries, changes to the calendar resulted in discrepancies between the Catholic, Protestant, and Orthodox churches, differences that still persist. While Latin-rite Catholics follow the Gregorian calendar, in the East the tradition of calculating liturgical dates according to the Julian calendar has been maintained.
“The process of changing the calendar, which began in 1582 with Pope Gregory and was completed to a certain extent in 1923 with the adoption of the new calendar by some Orthodox churches, was not without difficulties,” Kostas Mygdalis, consultant to the Orthodox Interparliamentary Assembly (IOA), explained in an interview with ACI Prensa, CNA’s Spanish-language news partner. “It provoked controversies among the faithful and between the churches and state authorities, consolidating polarizing divisions” that still persist, he added.
Mygdalis is also one of the key figures of the interfaith working group Pasqua (Easter) Together 2025, which seeks to promote the common celebration of Easter between Orthodox and Catholics. Last September, Pope Francis received the members of this ecumenical initiative and expressed his desire to agree on a common date for the celebration of Easter between Catholics and Orthodox. Interestingly, this year both Easters — Catholic and Orthodox — fall on the same date, April 20, due to the alignment of the Julian (used by the Orthodox) and Gregorian (followed by Catholics and other Christian denominations) calendars.
For Mygdalis, the joint celebration of Easter in 2025 should not be seen as just a calendar agreement but as an opportunity to place Christ at the centre of the Christian faith. “The time has come to make a strong appeal to the churches to unify the date of Easter,” he said. He also emphasized that the central message must be the need for unity in the world: “The world needs unity. A common date for Easter is a step toward this unity.”