What are the reasons that the oriental Orthodox Churches are not in communion with the Eastern Orthodox Churches?
The Oriental Orthodox Churches mentioned here and including the Coptic, Ethiopian, Syrian, Armenian, and the Indian Churches are very close to the Eastern Orthodox churches, but not in full unity with them. The faith is the same but division came because of a misunderstanding that occurred among the church members at the council of Chalcedon. The Coptic Church was misunderstood at the Council of Chalcedon in 451 AD. The Coptic Church was accused of following the teaching of Eutyches, who believed in Monophysis. This doctrine maintains that the Lord has only one nature; the Divine nature only. The Coptic Church refuses and rejects the teaching of Eutyches and believes that our Lord Jesus Christ is perfect in His divinity and perfect in His humanity. His divinity parted not from His humanity not for a single moment nor a twinkle of an eye. Therefore, our church believes in Miaphysis and it was clear that the council of Chalcedon had not been held to discuss a dogmatic creed but for political reasons. Pope Leo of Rome wanted to declare himself as supreme over all the churches of the world including the church of Alexandria. Perhaps the Council of Chalcedon understood the Church correctly, but they wanted to exile the Church, to isolate it and to abolish the Egyptian, independent Pope, who had contended that Church and State should be separate. Despite all of this, the Coptic Church has remained very strict and steadfast in its faith. Whether it was a conspiracy from the Western Churches to exile the Coptic Church as a punishment for its refusal to be politically influenced, or whether it was just misunderstanding, the Coptic Church has always felt a mandate to reconcile semantic differences between all Christian Churches. Today, dialogues are taking place between the Oriental and the Eastern Orthodox churches to get into full unity and communion together since actually the faith is the same.