Faith in History / Sean Gallagher

Although he lived 1,800 years ago, St. Irenaeus remains relevant today

Although he is the doctor of the Church who goes back farthest in Church history, St. Irenaeus of Lyons is one of the most recent saints to be given this title.

He is thought to have been born between the years 120 and 130 in present-day Turkey and died as a martyr in present-day Lyons, France, around 202. But he was only named a doctor of the Church in 2022 by Pope Francis. The Church celebrates his feast on June 28.

Irenaeus’ formation in the faith reaches back to the earliest days of the Church. He was born in Smyrna, today the city of Izmir in Turkey. It is thought that he may have been a spiritual student of St. Polycarp, the bishop of the city at the time. Polycarp, in turn, according to an ancient tradition, was said to have been taught by St. John the Apostle.

Understandably, St. Irenaeus emphasized in his writings that the way to determine authentic Christian beliefs is to trace them to apostolic origins.

It was important for Irenaeus to do this because many groups had emerged across the Roman Empire claiming to represent true Christian teachings that differed from those taught by the nascent Church.

Most of these groups, which would ultimately be determined to hold and proclaim heresies, were what historians and theologians came to call “gnostics.”

This term is rooted in the Greek word “gnosis,” which means “knowledge” in English. There were a wide variety of gnostic groups rivaling the Church in the first few centuries of its history. Each in their own way claimed to have a secret “knowledge,” which, when known, would free knowers from the trials of this fallen world and open them to eternal life.

Irenaeus addressed the beliefs of a particular gnostic group led by a man named Valentinian in his work known as Against Heresies. Through the course of five volumes in this work, Irenaeus sought to lay out this group’s beliefs, how they are false and to argue for the veracity of authentic Christian teachings rooted in Gospels with true apostolic origins.

Many gnostic groups in Irenaeus’ time put forth their own Scriptures which they claimed were written by Apostles. In his writings, Irenaeus makes an early argument for the apostolic authenticity of only the four Gospels that are in the New Testament that we have today. He also emphasizes the continuity of the Old Testament and the New Testament, which the gnostics commonly denied.

Gnostics in many instances also showed dualistic tendences, calling good only that which was spiritual while naming what was physical as evil.

Irenaeus staunchly opposed such dualism, proclaiming strongly both the full humanity and divinity of Christ, a central Christian belief which would later become known as the incarnation.

One of Irenaeus’ most famous quotes is found in the fourth book of Against Heresies in which he made arguments for the incarnation and against gnostic dualism. Translated in various ways, it is most commonly known as, “The glory of God is man fully alive.”

In defending the incarnation, Irenaeus was also placing a high value on creation as put in order by God the Creator. That includes valuing the human body created as it is and taken on by the Second Person of the Blessed Trinity.

This ancient teaching of Irenaeus is especially relevant today as it has become more common to believe that the human body as created by God is irrelevant to a person’s identity. Such opinions echo in part the views of the ancient gnostics, who held that the human body is an obstacle to overcome for people to achieve their ultimate destiny.

Irenaeus invites us to see the human body from a different perspective—from the perspective of God in Christ. He took on a created human body. The glory of God showed forth through it in the babe whose birth in Bethlehem we will celebrate on Christmas.

Each of us was created in the image of God, and in baptism we became his adopted sons and daughters. With the help of God’s grace, may his glory shine forth through us in our daily lives of faith.
 

(Sean Gallagher is a reporter and columnist for The Criterion.) †