Meet St. Irenaeus of Lyon

When Pope Francis surprised the Catholic world on October 7, 2021, announcing that he was about to make Saint Irenaeus of Lyon a Doctor of the Church, the reasons he gave weren’t that surprising. 

After all, the pope’s stated reasons for the declaration made sense. Saint Irenaeus (c. 130-c. 202 AD) came from the East (modern Turkey) but served as a bishop in the West (modern France). Both Catholic and Orthodox Christians have revered the man and studied his writings for thousands of years. Honoring Irenaeus would therefore seem a perfect way to take another step in the long-overdue reconciliation between the Churches of the East and the West. Since Pope Francis was addressing the Saint Irenaeus Working Group, a group of both Orthodox and Catholic theologians, Francis’ announcement to honor their patron was probably not unexpected to them.

Pope Boniface VIII began the tradition of declaring Doctors of the Church in 1294. The names of the four men he chose surprised no one: the Biblical scholar Saint Jerome of Stridon; the honey-tongued bishop Saint Ambrose of Milan; the monk-turned-bishop-turned-pope Saint Gregory the Great; and the prolific writer and famous convert Saint Augustine of Hippo. Who would deny that those men had been enlightening the minds and hearts of Catholics for centuries?

Typically, papal decisions like these take hundreds of years of consideration. Almost three hundred years passed after the death of Saint Thomas Aquinas before Pope Pius V declared the brilliant Dominican to be the fifth Doctor in Church history. On the other hand, Pope Gregory XVI declared Saint Alphonsus Liguori to be a Doctor of the Church less than a hundred years after Alphonsus’ death, something of a speed record in the history of the Church. Tradition says that Alphonsus vowed to never waste a moment of his life, and the incredible number of works that he produced—including his famous Moral Theology for priest-confessors—would seem to prove that he fulfilled that vow and earned the title of Doctor. 

It would be hard to believe that anyone was scandalized when twentieth-century and twenty-first century popes opened the door for women Doctors of the Church. After all, Saint Catherine of Siena (declared by Pope Paul VI), Saint Teresa of Avila (also declared by Pope Paul VI), and Saint Hildegard of Bingen (declared by Pope Benedict XVI) were the sort of take-charge, holy women who probably frightened weak men in their own lifetimes. Saint Therese of Lisieux was declared a Doctor of the Church by Pope John Paul II, but Pope Pius X had already showered the Carmelite nun with praise within a few decades of her death.

All told, the example of the thirty-six people who have already been proclaimed Doctors make it easy to see that the bishop of Lyon did not merit the title merely to appease East-West tensions. There are other reasons for the Church to encourage twenty-first century Catholics to turn to this second-century bishop.

Irenaeus famously served as a mediator over a debate about the proper date to celebrate Easter. Early Christians disagreed for centuries over which day of the week and which date relative to the Jewish feast of Passover should be used in the annual celebration of the Resurrection of the Lord. Irenaeus served as a peacemaker, mediating an agreement between the pope and a group of Christians over this difficult issue.

Irenaeus also wrote that Matthew, Mark, Luke, and John are the only Gospels that we, as Christians, should accept. Those false gospels that pseudo-Christians keep trying to present as “lost” were discounted by Irenaeus and other Catholics as nonsense as far back as the second century.

But those are not Irenaeus’ greatest contributions as a teacher and leader of the Church. Instead, his writings continue to be a model for apologists trying to provide a Christian response to the heresies of the day.

During Irenaeus’ lifetime, Gnosticism was one of the most serious heresies confronting the Church. Gnosticism was a mixture of ideas from several religions, including Buddhism, pantheism, Hinduism, Judaism, and Christianity. But one thing that Gnostic teachers had in common with New Age gurus of today is an emphasis on secrecy. Only those who had been fully initiated were allowed access to all the “secret knowledge” known by the most important Gnostic leaders. Access to such knowledge, obviously, came at a price.

Irenaeus vowed to “strip the fox”, that is, reveal all the secrets of Gnosticism to the public and let everyone see it for what it was: a pack of confusing lies that only used Christian terms to hide the foolishness that lay beneath. In his famous Against Heresies, Irenaeus did just that. He exhaustingly laid out secret Gnostic teachings, compared them with the Catholic faith, provided proof for his positions from Scripture, and concluded with further proofs of the beauty and truth of the Gospel.

Although it may seem somewhat tedious today to read Irenaeus’ careful examination of beliefs that are no longer leading Christians away from Christ, there are still passages that are relevant today. In Book 1, Chapter 11, for example, Irenaeus made fun of the complicated and inconsistent names used in Gnosticism. To show how ridiculous it all was, he coined his own silly nomenclature, using words like “cucumber” and “gourd” to parallel similar Gnostic terms. This is not unlike the best of Catholic apologists today, who respectfully explain their opponents’ beliefs, but who are not afraid to point out ideas which make no sense and even use humor to do so.

In the end, Irenaeus achieved what he set out to do: he showed the truth of the Gospel and the foolishness behind a false religion that had captivated many of his contemporaries. For that reason alone, Saint Irenaeus of Lyon is a worthy Doctor of the Church in any age.

(Editor’s note: This essay was posted originally at CWR on October 11, 2021.)