New Testament Concepts of the Christian Ekklesia – Should They Still Apply Today? The Eastern Orthodox Answer

Wikipedia notes: The Eastern Orthodox Church, officially the Orthodox Catholic Church, and also called the Greek Orthodox Church or simply the Orthodox Church, is the second-largest Christian church, with approximately 220 million baptized members. It operates as a communion of autocephalous churches, each governed by its bishops via local synods. The church has no central doctrinal or governmental authority analogous to the head of the Catholic Church (the pope). Nevertheless, the Ecumenical Patriarch of Constantinople is recognized by them as primus inter pares (“first among equals”), a title formerly given to the patriarch of Rome.

Orthodoxy’s claim to be the true church is that it alone follows the seven ecumenical councils without additions made to the statements of these councils. An addition was made to the statement of the Nicene Council that was not approved by a full ecumenical council saying the Holy Spirit proceeded not only from the Father but also from the Son. The Orthodox Churches, comprised mostly of churches in the east, whereas Catholic churches are mostly in the west, split from the Roman Catholic Church over such doctrinal issues as the procession of the Holy Spirit and the claim that the Roman Bishop (the Pope) was supreme. This occurred in 1000 AD.

The dispute to this church being the only true church is that the vast majority of Christians hold basically to the doctrines of the seven ecumenical councils. Minor differences, like whether the Holy Spirit proceeded from the Father and the Son, are hardly sufficient to make one group orthodox and another unorthodox.

The one true church can only be the believers from within any denomination who hold to the true Lord Jesus Christ. That means the true church is transdenominational, it spans all denonminations.