ROME – In a decision seen as an act of defiance towards the Russian Orthodox Church, which also has the effect of promoting closer ties with Roman Catholics and other Western branches of Christianity, the Orthodox Church of Ukraine has decided to move Christmas to Dec. 25.

Traditionally, Ukrainian Christians, the bulk of whom are Orthodox, have celebrated Christmas on Jan. 7, along with other predominantly Orthodox nations, including Russia, which invaded Ukraine in February of last year.

On May 24, the Council of Bishops of the Orthodox Church of Ukraine voted nearly unanimously to switch from the Julian calendar to the Gregorian calendar as regards most major feasts, except for Easter and a handful of other feast days, such as the feast of the Trinity.

In a statement following the Council’s decision, Metropolitan Epiphany, head of the Orthodox Church of Ukraine, said the decision “is not an easy one, we have been coming to it for a long time, gradually, step by step, and we are making it carefully.”

However, Epiphany said the decision was “as necessary as the decision to introduce the Ukrainian language in worship instead of the traditional Slavic language, to introduce an autocephalous structure of the Church’s life instead of centuries of subordination.”

The Ukrainian Greek Catholic Church, one of several Byzantine-rite churches in full communion with Rome, was the first to make the switch to a new calendar in early 2023.

Adherents to Orthodoxy still follow the Julian calendar, while the Catholic Church and most of the world follow the Gregorian calendar, introduced via papal bull Pope Gregory XIII on February 24, going into effect in October 1582 as a modification of, and replacement for, the Julian calendar.

The transition from the Julian calendar without making a change regarding the celebration of Easter is called the “New Julian” calendar, which is already used by many Orthodox churches in Europe.

In Ukraine there are two primary branches of Orthodox, the autocephalous Orthodox Church of Ukraine, and the Ukrainian Orthodox Church of the Moscow Patriarchate – a branch of Orthodoxy in Ukraine that reports to Moscow.

Following their recent vote, as of Sept. 1, which marks the beginning of their new church year, the Orthodox Church of Ukraine (OCU) will celebrate Christmas on Dec. 25, rather than on Jan. 7.

The Orthodox Saint Nicholas Day will now take place on Dec. 6, and the church will join Catholics in celebrating the feast of the Epiphany on Jan. 6.

In a decree announcing their decision, the OCU said they made the decision to switch the date of their observance of Christmas not only because the Julian calendar is of secular origin and “has no sacred significance,” but also because it is associated with Russian Orthodoxy.

“In the modern realities of the existence of the Orthodox Church of Ukraine in Ukrainian society, especially in connection with the aggressive Russian war against Ukraine,” the demand for a change in the calendar increased “significantly,” they said.

For centuries, the traditional Julian calendar “was perceived as one of the main identifiers of Ukrainian church culture. At first, it was a sign of resistance to Latinization, and after the Bolshevik revolution, it was also a sign of resistance to the Soviet system,” they said.

However, the social and cultural context in Ukraine has changed dramatically since then, the OCU’s statement said.

Nowadays, it said, the Julian calendar “is perceived by the majority not so much as connected with ancient Ukrainian traditions, but as connected with Russian church culture. After all, the Orthodox Churches that support the Orthodox Church of Ukraine use the modern calendar, while its opponents, and primarily the Russian Orthodox Church, follow the old calendar.”

“Therefore, the desire to preserve and affirm one’s own, Ukrainian, spiritual identity, protection from the aggression of the ‘Russian world,’ requires a timely decision – to join the majority of Local Orthodox Churches – in introducing into use the New Julian calendar, as more accurate astronomically and ecclesiastically accepted, with the preservation of the traditional Easter,” the statement said.

The outbreak of the Russia-Ukraine war last year has caused a fracture inside the Orthodox world, with several local Russian Orthodox churches opting to break away from the Moscow Patriarchate over Russian Orthodox Patriarch Kirill’s support of the war, requesting to switch jurisdiction to the Ecumenical Patriarchate of Constantinople, led by Patriarch Bartholomew, instead.

Traditionally, the Ecumenical Patriarchate of Constantinople and the Moscow Patriarchate have been at odds, seen as representing two different strains of Orthodoxy, with Moscow accusing the former of being too indulgent of the West and, therefore, of Western secular values.

However, with Russia’s invasion of Ukraine last year, this sentiment has changed among many Orthodox, sparking a significant shift in sentiment among Ukrainian Orthodox, particularly those who are loyal to Moscow.

Last spring, shortly after the war broke out, priests within the Ukrainian Orthodox Church of the Moscow Patriarchate began collecting signatures for a petition to oust Russian Orthodox Patriarch Kirill from his position of leadership over his support for Russia’s invasion of Ukraine.

This follows a similar petition launched at the beginning of the war that was signed by nearly 300 Russian Orthodox priests, including several prominent members of the Russian Orthodox Church, and which urged Kirill to condemn the war, which over a year later, he still has not done.

Ecclesial tensions in Ukraine are also being felt at the political level, as the Ukrainian parliament debates a bill banning all activities of the Moscow Patriarchate in Ukraine.

Despite his frequent condemnations of Russia’s invasion, the leader of the Ukrainian Greek Catholic Church, Major Archbishop Sviatoslav Shevchuk, has condemned the bill, saying it is not only problematic on grounds of religious freedom, but would have the counterproductive effect of turning supporters of Russia into martyrs.

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The UOC’s statement specified that despite the shift in calendar, parishes that wish to continue following the old Julian calendar for economic or other reasons may do so, but the decision must be approved by a two-thirds majority of community members and it must be “properly documented.”

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