St. Irenaeus, born in Asia Minor around the year 130, was a spiritual “grandchild” of St. John the Evangelist, through his pupil St. Polycarp of Smyrna, who taught Irenaeus in his youth. This close connection with apostolic teaching caused Irenaeus to be a staunch defender of Orthodox belief and concerned with faithfully passing on the Tradition of the Church in a time when Christianity was being persecuted by pagan emperors on one hand and besieged by numerous heretical ideas on the other.
After completing theological and philosophical studies, Irenaeus was sent to be a priest in Lyons, the most populous city of Gaul at the time and an important trade center. St. Pothimus, the first bishop of Lyons, held Irenaeus in high regard, and when he desired to send a petition to Patriarch Eleutherius of Rome regarding the Montanist sect, Irenaeus was chosen to deliver it.
According to God’s plan, Irenaeus was on this mission when a brief period of persecution against Christians occurred in Lyons. This was in the year 177, during the reign of Marcus Aurelius, and may have simply been a show of imperial power against this young, illegal religion. The 90-year-old Bishop Pothinus suffered martyrdom after being beaten during questioning by the Roman soldiers, and when Irenaeus returned to Lyons, it was to take Pothimus’ place as bishop.
Lyons did not suffer persecution again during the more than twenty years of Irenaeus’ episcopacy, leaving him the freedom to spread the Christian faith by sending missionaries to other parts of Gaul; to preach, teach, and write theological arguments refuting various heresies (particularly Gnosticism); and to urge leniency and tolerance regarding variations in practice (particularly the Quartodecimans’ observation of Easter on the second day after the Jewish Passover rather than on the Sunday observed by most of the Christian world).
St. Irenaeus’ death, as a martyr, took place around the year 202, along with some nineteen thousand others, in the time of the Emperor Severus. His relics were buried in the crypt of the Church of St. John in Lyons, where they were venerated by Christians for over 1300 years until the shrine was destroyed by Calvinists in 1562. To those iconoclasts and others of our day, our holy father Irenaeus teaches us through his writing Against the Heresies:
We have learned the plan of our salvation entirely from the men through whom the Gospel came to us. At first they proclaimed it abroad; then later, by the will of God, they wrote it down for us in the Scriptures to be the foundation and pillar of our faith…Now it is within the power of anyone who cares to find out the truth, to know the tradition of the Apostles, professed throughout the world in every church…Seeing, therefore, that we have such testimony, we do not need to seek elsewhere the truth which it is easy to find in the Church. For the Apostles, like a rich man at a bank, deposited lavishly with her all aspects of the truth, so that everyone, whoever will, may draw from her the water of life. For she is the door to life, and all others are thieves and robbers. For this reason we must shun them and love the things of the Church with the utmost diligence and keep hold of the tradition of the truth…This is the course followed by the [Gallican] people who believe in Christ and have salvation written in their hearts by the Spirit without paper or ink, but who guard carefully the ancient tradition. For they believe in one God, the Creator of heaven and earth and of all things therein through Christ Jesus, the Son of God, who for his surpassing love towards his creation underwent birth from a virgin, uniting man through himself to God, and who suffered under Pontius Pilate and rose again and was received up in splendor, and who shall come in glory, the Saviour of those who are saved and the Judge of those who are judged, to send into eternal fire those who pervert the truth and despise his Father and his coming.