The largest bloc in the 260-million-strong congregation of Orthodox Christianity is no longer a single religious body governed from Moscow. The implications of this decision, announced by ecclesiastical authorities Thursday evening, are far-reaching, dislodging a cornerstone of the Orthodox Church that was established more than three centuries ago.

In a statement expected for several weeks, a synod convened by the Ecumenical Patriarch of Constantinople Bartholomew I—designated “the first among equals” in the global hierarchy of Orthodox Christian prelates— acknowledged the right to independence of the Ukrainian Orthodox Church, which has been overseen by religious officials in Moscow since 1686.

The synod formally recognized the legitimacy of the separatist Kiev Patriarchate of the Ukrainian Orthodox Church, established in the ruins of the Soviet Union 26 years ago and long treated as a pariah. The group also affirmed the priestly status and authority of the Kiev Patriarchate’s militant founder and leader, 94-year-old Patriarch Filaret. In addition, the religious leaders revoked the 1686 act of union between the Russian and Ukrainian congregations.

View Images Godmother Ala Oriekhovych comforts Alisa, age three months, in her mother Taisia Melnyk's arms during her baptism at the Life Spring Church. Photograph by Brendan Hoffman

Together, Russian and Ukrainian Christians number more than the combined total of all other Orthodox congregations worldwide. Ukrainians currently account for one-fourth of the Moscow Patriarchate’s 136 million faithful and one-third of its 18,000 parishes. The split poses the “worst crisis” in the thousand-year annals of the Orthodox Church, according to informed observers.

The dispute also pits supporters of Russian President Vladimir Putin against his chief regional critic, President Petro Poroshenko of Ukraine. Both are viewed as exploiting the church crisis in what amounts to a political vendetta, inflamed by Russia’s forcible annexation of the Crimea in 2014 and its ongoing military intervention in restless Eastern Ukraine.

Poroshenko called the synod’s decision “a victory of good over evil.” The Moscow Patriarchate, he said, “was a direct threat to the national security of Ukraine.”

In recent years, the Kiev Patriarchate’s ranks have grown to include an estimated 29 percent of the Ukrainian faithful, while those under Moscow’s wing comprise 13 percent. Another 26 percent describe themselves as “just Orthodox” or affiliated with smaller branches of the church.

In September, when it became clear that Ukrainian “autocephaly”—the canonical term for independence—was imminent, the Moscow Patriarchate retaliated by suspending liturgical prayers for Bartholomew, banning its priests from co-presiding with Constantinople bishops at religious services, and ending participation in assemblies, theological dialogues, and commissions chaired by Constantinople representatives.

The escalating dispute has prompted fears that violence may ensue. Russian websites have circulated unfounded reports of Ukrainian nationalists storming the Kiev-Pechersk Lavra, a famous monastery. Some clerics in areas loyal to the Moscow Patriarchate, including the monastery, are said to have urged parishioners to “defend their churches.”

Yet despite its origin in tensions rooted deeply in Orthodox history, the stand-off has no liturgical or theological dimensions, almost all parties agree. In this the crisis closely resembles its counterparts elsewhere in the larger universe of mainstream religion: a precipitous decline in active membership, institutional fragmentation, and the subordination of spiritual concerns to politics.

View Images The founding of the Kyiv-Pechersk Lavra traces back to the 11th century, when a monk took up residence in a cave. The cave is now part of the Church of St. Theodosius, where a liturgy service begins at 1:00 a.m. Photograph by Brendan Hoffman

Russia and Ukraine, the two nations at loggerheads over Orthodox religious authority, are also among the world’s most secularized. While identification with national churches remains very high in almost all Orthodox-majority nations—measuring 71 percent of the total population in Russia and 77 percent in Ukraine—active religious practice is exceedingly low.

A 2016 public opinion survey conducted by the Pew Research Center revealed that only 15 percent of Russians and 20 percent of Ukrainians describe religion as “very important.” Just six percent of Russians and 12 percent of Ukrainians attend religious services weekly, and only 18 and 28 percent pray daily. By contrast, 52 percent of Americans regard religion as very important, 31 percent attend church every week, and 57 percent pray every day.

In short, popular identification with Orthodox churches is mostly about symbols of nationhood and has very little to do with religious beliefs.

Worldwide, Orthodoxy has also been plagued by declining numbers relative to global population. In 1910, 20 percent of the world’s Christians were Orthodox. Today, according to Pew, the figure is 12 percent. It’s against this backdrop that differences between religious officials in Moscow on the one hand, and Ukraine and the Constantinople Patriarchate on the other, have veered into full-blown crisis.

“The Patriarch of Constantinople has no jurisdiction over Ukraine under canonical law,” asserts Vladimir Legoyda, Director of Synodal Department for Church Relations with Society and the Media in Moscow. “Bartholomew cites the existence of historical documents proving that the accord in 1686 was meant to be temporary.” But no such documents have been produced, Legoyda maintains, adding that terminating the relationship after more than three centuries is “absurd.”

“It would be as if we said Alaska is still Russian because its sale to America occurred a long time ago under another regime.” (The sale was negotiated in 1867 by then U.S. Secretary of State William H. Seward.)

Russian ecclesiastical officials bristle at frequent accusations that the Moscow Patriarchate is a pawn of Putin, invariably supporting his domestic policies and representing his interests abroad.