Great Russian Schism

Raskol (Russian: раскол, Russian pronunciation: [rɐˈskol], meaning "split" or "schism") was the event of splitting of the Russian Orthodox Church into an official church and the Old Believers movement in the mid-17th century. It was triggered by the reforms of Patriarch Nikon in 1653, which aimed to establish uniformity between Greek and Russian church practices.

The members of an influential circle called the Zealots of Piety (Russian: Кружок ревнителей благочестия Kruzhok revnitelei blagochestiya) stood for purification of Russian Orthodox faith. They strove to reform Muscovite society, bringing it into closer accordance with Christian values and to improve church practices. As a consequence, they also were engaged in the removal of alternative versions and correction of divine service books. The most influential members of this circle were Archpriests Avvakum, Ivan Neronov, Stephan Vonifatiyev, Fyodor Rtishchev and, when still Archbishop of Novgorod, Nikon himself, the future Patriarch.

With the support from the Russian Tsar Alexei Mikhailovich, Patriarch Nikon began the process of correction of the Russian divine service books in accordance with their modern Greek counterparts and changed some of the rituals (the two-finger sign of the cross was replaced by the one with three fingers, "hallelujah" was to be pronounced three times instead of two etc.). These innovations met with resistance from both the clergy and the people, who disputed the legitimacy and correctness of these reforms, referring to theological traditions and Eastern Orthodox ecclesiastic rules. Ignoring these protests, the reforms were approved by the church sobors in 1654–1655. In 1653–1656, the Print Yard under Epifany Slavinetsky began to produce corrected versions of newly translated divine service books.

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