Although information is sparse, it is believed that St. Irenaeus of Lyon was born between AD 115 and 125. His birthplace was in the area of Proconsular Asia or a surrounding province. It is believed that while he was still very young he saw and revered the teachings of the holy Bishop Polycarp who had heard the teachings of the Apostle John. After Ireneaus became a priest he was sent to Lyon, the most populated commercial city in Gaul (France). He served under St. Ponthinus, the Bishop of the church in Lyon who was killed in the persecution of that city. Irenaeus traveled to Rome, where he met with the Pope, sharing information about the martyrdom of Ponthinus.
Irenaeus traveled back to Lyons where he was installed as the Bishop of the church. He wrote five books in which he exposed Gnosticism, the ravages of the persecution, the false inner doctrines of the various sects, and finally, he compared these with the apostolic teachings. His works and writings formed the fundamentals of Christian theology which earned him the title of one of the Fathers of the Church. It is believed that he died in the year AD 202, and that he was buried in a crypt under the altar of the Church of St. John which came to be known as the Church of St. Irenaeus. Unfortunately, the crypt was destroyed by the Calvinists in 1562, destroying all relics of the saint.
The feast day to honor St. Irenaeus is June 28.