4. And the action of heresy, which was so effective in bringing out the function of the teaching church, was not without force in extending and corroborating the function of the ruling church. The first synods of which we have mention are those assembled in Asia Minor towards the end of the second century against the diffusion of Montanism.(253) But what through the loss of records has been mentioned only in this one case must have taken place generally, since it is obvious that as soon as erroneous doctrines spread from one diocese to another, they would call forth joint action against them. Since then heresies have been the frequent, almost the exclusive, cause of councils. The parallel is fruitful in thought, which is suggested between the action of error in eliciting the more precise expression of the truth which it abhors, and its action in strengthening the governing power of the body which it assaults. In the one case and in the other the result is that which it least desires and intends; heresy, disbelieving and disobeying, is made to perfect the faith and build up the hierarchy. Now to sum up our sketch of the internal history of the Christian Faith in the seventy-four years which elapse from the accession of Marcus Aurelius to the death of Alexander Severus. At the first-named date we find that it had spread beyond the confines of the Roman empire, and taken incipient possession of all the great centres of human intercourse by founding its hierarchy in them. At the second date it has subdued the powerful and widespread family of heresies which threatened to distort and corrupt its doctrines, and has done this by the vigour of its teaching office, which combined in one expression the yet fresh apostolic tradition stored up in its churches, and the doctrine of its sacred scriptures; while it has well-nigh determined the number and genuineness of these, severing them off from all other writings. The episcopate in which its teaching office resides appears not as a number of bishops, each independent and severed, and merely governing his diocese upon a similar rule, but with a bond recognised among them, the superior principate of the Roman See. That is, as the teaching office itself is in them all the voice of living teachers, so its highest expression is the voice of the living Peter in his see. And this bond as discerned and recognised by the Asiatic disciple of S. Polycarp, the bishop of the chief city of Gaul, is so strong that he uses for it rather the term denoting physical necessity than moral fitness:(254) as if he would say: As Christ has made the Church, it must agree from one end to the other in doctrine and communion with the doctrine and communion of the Church in which Peter, to whom He has committed His sheep, speaks and rules. And so powerful is the derivation of this authority that he who sits in the place of Mark, whom Peter sent, punishes by degradation a bishop who disregards his sentence in the case