:The Christian Coptic Orthodox Church is a separate church that is part of the little-known group of Christians called the Oriental Orthodox. Oriental Orthodox churches are not the same as the more familiar Eastern Orthodox group, which includes the Greek and Russian Orthodox churches.
Most Americans are aware of the split in Christianity caused by the Reformation led by Martin Luther and his contemporaries in the 1500s. Many also know Roman Catholic and Eastern Orthodox Christians split over various issues in 1054. Few, however, are familiar with events in 451 that caused the Oriental Orthodox and the rest of Christianity to divide.
The early Christian church attempted to understand how believers should relate to Christ, what was required of worshippers and how to instruct converts to the faith by holding church councils to discuss and decide such matters. Chapter 15 in the New Testament Book of Acts reports the first of these meetings, known as the Council of Jerusalem, which decided whether Gentile converts must first be circumcised and whether they must also follow food laws and other regulations given to Moses.
More councils followed to deal with theological issues concerning the Trinity and the nature of Christ. Whether Jesus was human or divine was a frequent issue the early church attempted to understand. In 451, a council to discuss Jesus' nature was held at Chalcedon in Bithynia, today part of Turkey.
The theological argument concerned whether Jesus was only human, only God, both human and divine, human at one point and divine at another and so on, with every imaginable variation. A misunderstanding developed between the Oriental Orthodox churches — sometimes called the non-Chalcedonian churches — and the rest of the Christian world.
The Roman and Constantinopolitan delegates incorrectly believed the Coptic and other Oriental Orthodox churches said Christ had only one nature. The church as a whole insisted that Jesus had two natures — human and divine — which existed at the same time. What the Coptic churches and their compatriots actually said was Christ's two natures were inseparable. In other words, Jesus was always fully human and always fully God. The Oriental Orthodox mistakenly believed the rest of the Chalcedon delegates insisted Jesus had two distinct natures that were separated from one another.