Now to form a correct notion of the danger to which the Christian people at this time was exposed, we must have before us that it was contained in several hundred communities, each of them forming a complete spiritual society and government. These had arisen under the pressure of such hostility on the part of the empire that it is only in the time of the last emperor during this period, Alexander Severus, that churches are known to have publicly existed at Rome.(219) For a very long time all meetings of Christians and all celebration of their worship was secret. It is obvious what an absolute freedom of choice on the part of all those who became Christians this fact involved. Nor did that freedom cease when they had been initiated into the new religion. Their fidelity to the Christian faith was all through their subsequent life solicited by the danger in which as Christians they stood. Only a continuous freedom of choice on their part could maintain it. And not only did every temporal interest turn against it, but in the case at least of the more intellectual converts the activity of thought implied in their voluntary acceptance of a new belief served as a material on which the seductions of false teachers might afterwards act, unless it was controlled by an everliving faith, and penetrated by an active charity. The more these Christian communities multiplied, the more it was to be expected that some of them would yield to the assaults of false teachers. It is in just such a state of things that a great dogmatic treatise was written against Gnosticism by one who stood at only a single remove from the Apostle John, being the disciple of his disciple Polycarp. Irenæus, by birth a native of lesser Asia, enjoyed when young the instructions and intimate friendship of the bishop of Smyrna. In his old age he delighted to remember how Polycarp had described his intercourse with John, and with those who had seen the Lord: how he repeated their discourse, and what he had heard from them respecting the teaching and the miracles of that Word of life whom they had seen with their own eyes. “These things,” says Irenæus, “through the mercy of God I then diligently listened to, writing them down not on paper, but on my heart, and by His grace I ruminate upon them perpetually.”(220) Later in life he left Smyrna, and settled in Lyons, of which Church he was a presbyter when the terrible persecution of 177 broke out there. Elected thereupon to succeed a martyr as bishop, he crowned an episcopate of twenty-five years with a similar martyrdom. He wrote, as he says, during the episcopate of Eleutherius, who was the twelfth bishop of Rome from Peter, and sat from 177 to 192. After describing at length the Gnostic errors concerning the divine nature, he sets forth in contrast the unity of the truth as declared by the Church in the following words: