The Family Of Eastern Orthodoxy
The Holy Orthodox Autocephalous Church Of Epirus (or short: Greek Orthodox Church or Epirus) belongs to the Orthodox family of churches, known as Eastern Orthodox, specifically Greek Orthodox.
Generally, Christianity is divided mainly between Eastern and Western churches. The relationship between Byzantium (East) and Rome (West) had deteriorated gradually: In the ninth century, a schism between the Byzantine Church and the Church of Rome started to shape during the time of Patriarch Photius. In 1054, anathemas (mutual excommunications) were declared by both sides (Patriarch Michael and Cardinal Humbert) which lasted for centuries. By 1204, when the Crusaders captured Constantinople, the schism had become final. In 1965, following the Roman Catholic Vatican II Council, the anathemas were lifted by both sides in a spirit of ecumenism and mutual recognition.
The main theological differences and disagreements between Eastern Orthodoxy and the Church of Rome (Roman Catholic) are in the following areas:
Papal Supremacy: Roman Catholics consider their Pope the “Vicar of Christ”, while the Orthodox churches consider him only as "primus inter pares" (first among equals) in honor and pastoral Diakonia.
Papal Infallibility: Catholics follow a monarchical model of ecclesial polity, whereby pronouncements of the Pope made on behalf of the Church (ex cathedra) are considered infallible. Orthodox Christians follow a conciliar model, where church councils determine dogma, canons and policies.
There are also other minor differences between the two branches, such as regarding the rules of fasting; unleavened bread at Eucharist (West); manner of conferring confirmation; celibacy of clergy; divorce (not sanctioned in Roman Catholicism). The West has more of a scholastic approach, the East takes a mystical path to theological questions.