St. Irenaeus, A Father of the Church

The feast of St. Irenaeus (pronounced “ear-uh-NAY-us”) is celebrated in the summer. The first teachers of Christianity are collectively spoken of as "the Fathers,” and Irenaeus was one of the first Fathers of the Church. It is the extraordinary writings of this man that earned him a place of honor, works which laid the foundations of Christian theology and kept the young Catholic faith from the corruption of heresy.

Irenaeus was born around the year 125, in one of the maritime provinces of Asia Minor, in present-day Turkey. This is an area where the memory of the Apostles was strong and where Christians were already numerous. Irenaeus had the privilege of sitting at the feet of men who had known the Apostles. Of these, the one who made the deepest impression on him was St. Polycarp, a direct pupil of the apostle John. All through his life, Irenaeus told a friend, he could recall every detail of Polycarp's appearance, his voice, and the very words he used when telling what he had heard from John the Evangelist and others who had seen Jesus.

Irenaeus was sent to Gaul, modern-day France, to serve as a priest, and he eventually became a bishop.

The spread of a heresy known as Gnosticism led Irenaeus to thoroughly examine Gnostic doctrine. Gnosticism taught that the creator of the world of matter, the God of the Old Testament, was dark and brutal and was separate from the pure and spiritual God of light, depicted in the New Testament, from whom Jesus emanated. It taught that Jesus only appeared to be born and die, because He never would have allowed Himself to be contaminated by taking on human flesh. The Gnostic movement, with its denial of Christ's humanity, was problematic to the Church in one form or another for several centuries.

Irenaeus’ five-book discourse, Against Heresies, talks about the rebellious sects and the doctrines they promoted. Irenaeus utilized a systematic method of disputing heresies, ultimately contrasting them with the words of Scripture and the teachings of the Apostles. Above all, he cited the authoritative tradition of the Church of Rome, handed down from Peter and Paul through an unbroken succession of bishops. His books, written in Greek and quickly translated into Latin, were widely circulated, and from this time on, Gnosticism was no longer considered a serious threat.

While St. Irenaeus died around the year 203, his writings were used to dispute heretical teaching for many years after his death, earning him the title of “Church Father.”