True Orthodox church

However, in Greece in 1937 the Greek Old Calendarists "divided"; the reason for their division was a disagreement on whether the sacraments performed by members of churches which have adopted the reformed calendar are valid or not.

[3] In 1971, the Russian Orthodox Church Outside of Russia (ROCOR) tried to unite the factions of Greek Old Calendarists, but failed.

[3] Since 2000, the prospect of reconciliation of ROCOR with the Moscow Patriarchate aroused opposition from traditionalists opposed to union with a church tied to the Soviet and post-Soviet regimes ruling Russia.

[4] Ecumenism and calendar reform are frequently points of contention with the mainstream Eastern Orthodox Church.

Denominations that are usually included in "True Orthodoxy" are: The Russian Orthodox Autonomous Church (ROAC) through the late Metropolitan Valentine, stated informally that they no longer actively seek to join other True Orthodox churches, but would not refuse incoming dialogue.