The calendar introduced in the UGCC and the OCU is essentially Gregorian, but it is applied only to fixed holidays—these are the 12 major feasts, including Christmas, which is a public holiday, and all other feasts fixed to specific dates. However, this reform did not concern the Paschalion, which is movable. All holidays associated with Easter—Ascension, Pentecost, etc.—are currently celebrated according to the old Julian style.

Why is this? In Ukraine, the Greek Catholic Church synchronized its calendar reform with the OCU so as not to deepen the division among believers. It often happens that in one village, families belong to different denominations, so the churches tried to coordinate this process. At the same time, Greek Catholics outside Ukraine have moved to the Gregorian Paschalion completely, so they celebrate Easter together with the Catholics and Protestants of the West. The Mukachevo Greek Catholic Eparchy also decided to switch to the new Paschalion.

What is the difference in calculations? The Gregorian calendar takes the real astronomical equinox—March 21—as its starting point. The first Sunday after the first full moon after this date is Easter. In the tradition that the OCU and UGCC have so far kept as their starting point, the Julian equinox is used. It lags behind the real one by 13 days, thus falling at the beginning of April. Next, a nominal full moon is mathematically calculated, and the first Sunday from it is the date of Easter.

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There is another nuance: if this date coincides with the Jewish Passover or precedes it, then according to the Eastern tradition, one must wait for the next full moon. That is why the difference between the dates can reach up to 5 weeks. This restriction is based on the canons of the First Council of Nicaea, when the Church tried to distance itself from Jewish traditions. This was a serious discussion in early Christianity, where it was decreed: the Christian Pascha must take place after the Jewish Passover.

Discussions are currently ongoing regarding a common date. Ecumenical Patriarch Bartholomew and Pope Leo XIV (as well as his predecessors) speak about the need for consensus. One of the options is to establish a fixed date, for example, the third Sunday of April, since we celebrate an event, not a number on a calendar. The calendar is not a dogma of faith but a technical tool.

In the UGCC, there is a hope that there will be an agreement between Rome and Constantinople. The only problem is that in Orthodoxy there is no unity regarding this issue, as with many others. The Moscow Patriarchate and its satellites in Poland, the Czech Republic, or Georgia have broken or frozen relations with Ecumenical Patriarch Bartholomew of Constantinople and are maintaining isolation. Accordingly, Constantinople is forced to balance: whether to take leadership in the search for a common date or to look over their shoulder at churches that have no enthusiasm for this, partly due to geopolitical reasons.

In Ukraine, there are still parishes that hold to the old style. The Moscow Patriarchate celebrates Christmas on January 7, although it includes Romanian communities in Bukovyna that celebrate according to the new style together with Romania. In the OCU, several communities also remained (particularly in the Hutsul region, in Kosmach), where the transition caused conflicts.

This year, Easter does not coincide for all denominations in Ukraine because we still follow the Julian Paschalion. If the Pope and the Patriarch find a compromise, we will celebrate with the rest of the world. However, for the Moscow Patriarchate, the calendar is almost an element of doctrine. They are unlikely to go for a union with the Western world, even a symbolic one. Living in the West, they may serve in Catholic churches, but in Ukraine, they continue to call Catholicism a "heresy." For them, the old calendar is a marker of identity that they have elevated to the status of church doctrine.

 The author's opinion reflects the author's subjective position. The editors of "Tvoe Misto" do not always share the thoughts expressed in the op-eds and are ready to provide those who disagree with an opportunity for a reasoned response.