If we refer to Acts 11:26 we are told this is where the apostles were first called Christians. However, scripture does not directly state any definition of what Christianity is, although we are given hints we would have to look to disciples of the apostles. Specifically we should look at St. Ignatius of Antioch, since they were first called Christians in Antioch and St. Ignatius was taught and ordained bishop of Antioch by the apostles. His writings should reflect that which he was taught as well as shine a light on what Christianity truly is.
“I exhort you to be careful to do all things in the harmony of God, the bishop having the primacy after the model of God and the priests after the model of the council of the apostles, and the deacons (who are so dear to me) having entrusted to them the ministry of Jesus Christ, who from eternity was with the father and at last appeared to us.” (Letter to the Magnesians, Ch.6)
Ignatius teaches the same thing Clement taught in his letter to the Corinthians, to exercise caution, to follow the bishops and priests, practice as has been taught, or as Ignatius says the “harmony of God.” The harmony of God, as described by Clement and Ignatius, is what the Orthodox Church has believed and practiced for the last 2,000 years. Why? Like Clement and Ignatius, we follow the hierarchal structure of the church, we perform the ministrations, as Clement teaches. We have record of our apostolic bishops, and what we (the Coptic Orthodox Church) have practiced and believed since our foundation by St. Mark in mid first century. This is important in demonstrating that through everything, our church has not been overcome, just as Christ stated in Mt. 16:18.
Ignatius strengthens his tone when he speaks of those outside the church: “Anyone who is within the sanctuary is pure and anyone who is outside is impure, that is to say, no one who acts apart from the bishops, the priests, and the deacons has a clear conscience.”
(Letter to the Trallians, Ch.7) A very harsh reality has been presented to us by Ignatius. Those who act apart from the bishops, priests, and deacons are essentially guilty. They are acting on their own authority according to their own will. In his letter to the Philadelphians, Ignatius makes one thing clear that: “All who belong to God and Jesus Christ are with the bishop. And those, too, will belong to God who have returned, repentant, to the unity of the church, so as to live in accordance with Jesus Christ. Make no mistake, brethren, no one who follows another into schism inherits the kingdom of God. (1 Cor. 6:9) No one who follows heretical doctrine is on the side of the passion.” (Letter to the Philadelphians, Ch.3)
Ignatius reveals to us that Christians are those who are “with the bishop.” Clearly meaning that if you do not follow a bishop, you do not follow Christ. To live in accordance with Christ is to belong to the “unity of the church.” This same thing is repeated in his letter to the Smyrnaeans, where Ignatius writes: “Shun schisms, as the source of troubles, let all follow the bishop as Jesus Christ did the Father, and the priests, as you would the apostles. Reverence the deacons as you would the command of God. Apart from the bishop let no one perform any of the functions that pertain to the church. Let that Eucharist be held valid which is offered by the bishop or by one whom the bishop has committed this charge. Wherever the bishop appears, there let the people be; as wherever Jesus Christ is, there be the Catholic (meaning universal) Church. It is not lawful to baptize or give communion without the consent of the bishop. On the other hand, whatever has his approval is pleasing to God. Thus, whatever is done will be safe and valid.” (Letter to the Smyrnaeans, Ch.8)
These “functions of the church” which Ignatius speaks of, are the sacraments. Ignatius cannot stress the importance of the bishop enough, and just how crucial it is for every Christian to follow their bishop. In one final example of the importance of bishops, Ignatius writes to us in a very direct manner. “For it seems to me that, when you are obedient to the bishops as you would be to Jesus Christ, you are living, not in a human way, but according to Jesus Christ, who died for us that by faith in His death you might escape death. You must continue, then, to do nothing apart from the bishop. Be obedient, too, to the priests as to the apostles of Jesus Christ, our hope, in whom shall be found, if only we live in Him. And, as ministers of the mysteries of Jesus Christ, the deacons should please all in every way they can; for they are not merely ministers of food and drink, but the servants of the church of God. They must avoid all reproach as they would beware of fire.” (Letter to the Trallians, Ch.2)
This post is by no means exhaustive, for a more in depth look refer to Reflecting God by John Apocalypse. We are also working on another book which deals with this very same topic.