A brief overview of its early history

Paul went on a series of missionary journeys around the eastern Mediterranean in what is now Orthodox Church territory. He attracted many Gentiles (non-Jews) to his movement. Paul organized churches in many of the areas' urban centers. He and his movement were in continual theological conflict with the Jewish Christian movement centered in Jerusalem. Paul ran afoul of Roman law, was arrested, and was transported to Rome where he was held under house arrest. He was executed there about 65 CE. Paul's churches survived his death and flourished.

Christian groups typically met in the homes of individual believers, much like home churches do today. There was no central authority, no standard style of organization at the local level, no dedicated church buildings or cathedrals. The Greek words episkopos (bishop, overseer), presbuteros (elder, presbyter) and poimen (pastor, shepherd) were originally synonymous terms which referred simply to the leader of a group of believers.₃ The Hebrew Scriptures (Old Testament) was their holy book; the Christian Scriptures (New Testament) had not been assembled. By the time that Jesus' original followers (now called Apostles) died, most of the Christians in the world were Gentiles following Pauline Christianity.

Another competitor to Pauline Christianity was Gnostic Christianity  -- a philosophical and religious movement with roots in pre-Christian times. Gnostics combined elements taken from Asian, Babylonian, Egyptian, Greek and Syrian pagan religions, from astrology, and from Judaism and Christianity. They claimed to have secret knowledge about God, humanity, and the rest of the universe of which the general population was unaware. They believed that the Jehovah of the Hebrew Scriptures was a defective, inferior Creator-God, also known as the Demiurge. He was viewed as fundamentally evil, jealous, rigid, lacking in compassion and prone to committing genocide. They viewed Jesus as a deity in human form, but not a human. They tolerated different religious beliefs within and outside of Gnosticism. Some Gnostics formed separate congregations; others joined existing Pauline Christian groups; still others were solitary practitioners.

There was considerable friction between the Christian movement and the Roman Empire. Christians were viewed as Atheists because they did not believe in multiple gods and goddesses. They were viewed as irresponsible citizens because many refused to sacrifice in the Pagan temples. Christians came under intermittent and serious oppression.

There was no single individual who spoke for all of Christianity. The only way in which the Church could resolve matters of belief and practice was to have all of the bishops assemble at a council to debate and vote. The first such meeting was the Council of Nicea, held in Asia Minor (now Turkey) during 325 CE. Only 318 bishops out of the approximately 1,800 Christian bishops then in existence attended. Most came from the Eastern half of the Roman Empire. ₂ Much of the debate at this and subsequent councils dealt with the precise nature of Jesus and his relationship to Jehovah and the Holy Spirit.

Circa 330 CE, Emperor Constantine decided to build a "New Rome" on the site of the Greek city of Byzantium (now at Istanbul, Turkey). It was called Constantinople. It became the center of the largely Christian empire. ₂ By this time, the church had evolved from a small, scattering of congregations to a geographically widespread church under the authority of many bishops.

Later in the fourth century, Emperor Theodosian issued a series of decrees or rescripts to "suppress all rival religions, order the closing of the temples, and impose fines, confiscation, imprisonment or death upon any who cling to the older [Pagan] religions." ₃ The period of relative religious tolerance under Paganism in the Roman Empire ended as non-Christian temples were seized and converted to Christian use or destroyed. Priests and Priestesses were exiled or killed. Pauline Christianity and Judaism were the only permitted religions. To follow another faith group was an offense punishable by death.

Church authority had became concentrated in the five bishops or patriarchs located in Alexandria, Antioch, Constantinople, Jerusalem and Rome. At the ecumenical council of 381, Rome was given the lead position, followed by Constantinople and then Alexandria. Their ranking followed the secular status of the bishops' cities in the Roman Empire. Each of the five patriarchs was totally sovereign within his sphere of jurisdiction. ₅

"Although the two regions belonged to the same church, they became increasingly remote from each other." ₄