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As Kyiv and Moscow clash on the battlefields of eastern Ukraine, a new front has opened up in the religious sphere.

Earlier this year Ukrainian's president launched a campaign to persuade Ecumenical Patriarch Bartholomew I, seen by many as the first among equals of Eastern Orthodox leaders, to grant Ukrainian clerics full ecclesiastical independence from the Russian Orthodox Church to which they have been tied for hundreds of years, The Washington Post wrote.

Ukrainian politicians see such a declaration, known as a "Tomos of Autocephaly," as a key step in consolidating their country's national identity. Russian religious leaders see it as an attack on Christian Orthodox unity and are fighting to stop it.

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It's in the midst of this religious tussle that The Associated Press has discovered a Russian digital espionage campaign targeting Bartholomew's top aides.

To hear the religious leaders in Moscow tell it, separating the Ukrainian Orthodox Church from Russia would spark the worst schism since Orthodox and Catholic Christianity parted ways nearly 1,000 years ago.

"This wrong step can only be compared to the division between East and West in 1054," senior Moscow Patriarchate official Hilarion Alfeyev said earlier this year. "If such a thing happens, Orthodox unity will be buried."

More immediately, the move would dramatically shrink the size and influence of the Russian Orthodox Church.

Even though Ukraine's population is several times smaller than that of its large Slavic neighbor, it is widely considered the more observant of the two and accounts for something like a third of the Russian Orthodox Church's approximately 35,000 parishes.

Perhaps just as important, the Russian Orthodox Church would lose its link to centuries' worth of tradition tied up in Ukraine's shrines and monasteries – a heavy symbolic blow.

Losing Ukraine "would be humiliating," said Katja Richters, an independent researcher who writes about the Russian Orthodox Church. "The Moscow Patriarchate would lose about 600 years of history."

That's what many Ukrainians argue.

"When a new state appears, when it becomes stable, it's a normal procedure for the Orthodox church believers to separate their church from the others," said Ukrainian historian Kyrylo Halushko. "This happened a few times in the 20th century: in Bulgaria, Serbia, the Czech Republic, Slovakia, Poland, etc. So it's a very logical step for independence to be given to Ukrainian Orthodox Church."

It may be logical, but it's not simple.

Leaving aside the theological wrangling over who has the authority to declare a church independent, there are important philosophical reasons for keeping the Ukrainian church in communion with its Russian counterpart.

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Christians are enjoined to unity (Galatians 3:28 says, in part, "Ye are all one in Christ Jesus.") The global Orthodox community is already fragmented and few leaders relish the prospect of cutting the world's largest Orthodox denomination in two. Even within Ukraine, some Orthodox clergy are leery of a process driven in part by secular politicians and the pressure of armed conflict between Ukraine and Russian-backed separatists in eastern Ukraine.

"Some of them say that it is difficult to have it done in a time of war and military confrontation with Russia," said Thomas Bremer, a professor of Eastern Churches Studies at the Faculty for Catholic Theology of the University of Muenster in Germany. "There is also a group of priests and bishops who would prefer to stay as a self-administering part of the Russian Orthodox Church.'"

The Ecumenical Orthodox Church also faces countervailing pressures. Bartholomew is 78 and some doubt he wants to cloud his legacy with a schism.

"I do not believe that Bartholomew wants to enter church history as the patriarch who has split his Church," said Bremer.

Anticipation is building on the Ukrainian side that Bartholomew will take the bold step of issuing a Tomos. Writing earlier this month for the Atlantic Council, an American think tank, Ukrainian commentator Kateryna Kruk said the ecclesiastic divorce "is almost a done deal."

Richters, the independent researcher, urged caution.

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"The Ukrainians seem very excited and they seem to think there will be a Tomos on Autocephaly in early September," she said. "They were fairly convinced 10 years ago and it didn't happen then."

Many read a trip by the Moscow patriarch to Istanbul planned for this week as a sign that the Russians are worried.

"This visit is not accidental," said Vasilios Makrides, a professor of religious studies at the University of Erfurt in Germany. "They must be nervous."

It's not clear whether the AP's spying revelations will have any impact on the debate over autocephaly, but Richters said it could heighten emotions that are already running high on both sides.

"(The hacking) would definitely be seen as hostile and tasteless and immoral," she said.