Among the usual classifications of Christian churches, some are insufficient, inaccurate, or clearly oriented in favor or against a particular church or group of churches. The most satisfactory classification, which is also the one adopted by the Catholicos Garéguine I and the most widespread among historians and theologians, part of the three theological orientations of Christianity that are:
– Catholicism (Roman Catholic Church and Eastern Catholic Churches born of Uniatism, including the Armenian Catholic Church),
– Protestantism (churches resulting from the Reformation, including the Armenian Evangelical Church, and the Anglican Church whose particularities make it close to the Catholic Church).
Orthodox churches include:
– the Orthodox Church (including the Greek Orthodox Church, the Russian Orthodox Church and the Georgian Orthodox Church);
– the Armenian Apostolic Church (described by its detractors as “Gregorian”);
– the Coptic Orthodox Church (the term “orthodox” is challenged by its detractors);
– the Ethiopian Orthodox Church (the term “orthodox” is also challenged by its detractors) and the resulting Eritrean Orthodox Church;
– the Syriac Orthodox Church (described as “Jacobite” by its detractors) and the Syro-Malankara Orthodox (Autonomous) and Malankara Orthodox (Autocephalous) Orthodox Churches that originate from it;
– the Assyrian Apostolic Church of the East (called “Nestorian” by its detractors) and the Malabar Orthodox (autonomous) Church which depends on it.
All these churches, geographically located in the Christian East, are of the same orthodox tradition in that they remain entirely faithful to the theological and spiritual tradition inherited from the Apostles, the Fathers of the Church and the Fathers of the Desert, in all its fullness, whether in its liturgical and spiritual aspects, or dogmatic and ecclesiological. These Churches, very attached to the inheritance of the undivided Church of the first centuries of which they have an acute conscience, did not wish nor knew the developments that the Catholic Church and the churches resulting from the Reformation thought good of initiate. Differences of opinion, usage and tradition have always existed between the Churches of orthodox tradition as in the undivided Church of the first centuries, but on points where a general agreement has not appeared and which are considered secondary. These divergences have never had any real theological or spiritual consistency, despite the polemics they may have led to, and have only “confirmed the agreement of faith” (Saint Irenaeus of Lyons). The only serious divergence is of a Christological order, in that the polemics around the Council of Chalcedon degenerated into reciprocal anathemas and put an end to the unity of the Christian East.