If he and other Ukrainians were once torn about dividing the church, the studied silence of the religious hierarchy in Moscow while Ukrainians died in a war provoked by Russia was, for many, the last straw. “The policy of the Moscow church over the past few hundred years has not been independent at all, it depends largely on the state,” Mr. Gorshkov said.

That has been especially true under President Vladimir V. Putin of Russia, who has maneuvered diligently in recent years to revive the idea that Moscow should be the capital for all Eastern Orthodox Christians, in effect making the Russian church an extension of his efforts to restore the country’s superpower status. Mr. Putin bolstered the church both to sell Russia as a bastion of “traditional values,” and to paint his Kremlin as heir to the holy traditions of the czarist empire.

Now, the Ukrainian church is on the verge of breaking away, threatening Mr. Putin’s imperial project in a direct and unintended consequence of Russia’s invasion of Ukraine.

“Say goodbye to the church of the empire,” said Sergey Chapnin, a religious scholar and frequent church critic. “The imperial dimension of Russia’s identity is extremely important,” he noted. “Autocephaly will be a strong blow to the imperial project, which is the only project that Russia has.”

The Russians, seething, are threatening to break entirely with the mother church, possibly provoking what some are calling the greatest schism in Christianity since the East-West divide in 1054. The Russian church argues that Bartholomew, who is based in Istanbul, has no right to remove the Ukrainian Orthodox Church from under the wing of the Moscow patriarchate without its consent.