True Orthodoxy

True Orthodoxy, or Genuine Orthodoxy (Greek: Γνησίων Ὀρθοδόξων Χριστιανῶν, "True Orthodox Christians", Russian: Истинно-Православная Церковь, "True Orthodox Church"), often pejoratively referred to as "Zealotry", is a movement within Orthodox Christianity that separated from the mainstream Eastern Orthodox Church over issues of ecumenism and Calendar reform since the 1920s.

Those who consider themselves a part of this movement are a minority of those who consider themselves to be Orthodox Christians, but True Orthodox writers have argued that in missionary areas such as the United States, Orthodox membership numbers may be overstated, with the comparative number of True Orthodox as up to 15% of the Orthodox population. In Russia, it has been claimed by some clergymen that up to a million Russians may be True Orthodox of different jurisdictions, though the Greek Old Calendarists and True Orthodox Russians are often cited at 1.7-2 million together.

Most True Orthodox Christians hold to a reading of history from the age of the Apostles to the 1920s as virtually identical to that of the mainstream Orthodox Church. True Orthodox Christians added the additional word "True" to distinguish themselves from those who they believe to have abandoned Orthodox doctrine after this period. (The term orthodoxy, from Greek ὀρθοδοξία, orthodoxia, already means "correct belief" or "right opinion".)

Most True Orthodox historians agree that the rise of the Ecumenical movement manifested through the change of the Church Calendar in the 1920s throughout the Orthodox world, as well as the 1927 capitulation of Metropolitan Sergius (Stragadorsky) to the Soviet authorities marked the formative period for True Orthodoxy, where those Orthodox who either would not go along with changes to the calendar or were disobedient to the civil authorities began to organize against the official church in earnest and create parallel hierarchies. While the early period in the history of True Orthodoxy marked a "grey area" in terms of how to regard those who went along with the innovation, today most True Orthodox disregard "World Orthodoxy"—at least the hierarchy—as part of the Church at all.

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Wikipedia