More than 1,800 years after his death, St. Irenaeus of Lyon is back in the news. At their November general assembly in Baltimore, Maryland, the U.S. bishops voted unanimously in agreement with a French initiative to name St. Irenaeus a doctor of the Church. Their approval has been passed on to the Vatican for consideration by Pope Francis.

If the motion succeeds, the second-century bishop will be named the 37th doctor of the Church, joining an elite group that includes St. Augustine, St. Thomas Aquinas, St. Teresa of Ávila, and St. Thérèse of Lisieux, among others. The Latin word doctor means “teacher,” and the Church’s doctors are considered its most important sources of doctrine.

St. Irenaeus is a most unusual case. A profoundly influential theologian from early in the Church’s history, many Catholic scholars confessed on social media that they were surprised by the U.S. bishops’ vote. They had assumed that St. Irenaeus already was a doctor of the Church. Some Catholic websites mistakenly identify him as one.

But he isn’t, yet, and that has more to do with the development of the title “doctor” than with his achievement.

Until the 16th century, there were only four saints so honored by the Western Church: St. Gregory the Great, St. Ambrose, St. Augustine, and St. Jerome.

In the centuries since, popes have sporadically added others. Most of the doctors, however, have been saints of the second millennium, who are better known to modern Catholics. The great teachers of the early Church are gaining due recognition at a slower pace.

The U.S. bishops’ unanimous vote, however, is evidence of the universal regard for St. Irenaeus.

“It’s not just what he knew. It’s also who he knew,” said Scott Hahn in an interview with Angelus News. Hahn is professor of Scripture and theology at Franciscan University of Steubenville, Ohio. “Irenaeus was a man as important for his connections as for his teachings. His authority is magnified by his spiritual lineage.”

As a young man, he learned the faith from St. Polycarp of Smyrna, who in turn learned the faith from St. John the Evangelist, who in turn learned the faith from Jesus Christ.

He grew up in Smyrna (Izmir in modern Turkey) and spent much time in the company of his master, Polycarp. Later in life, writing to a childhood companion, he recalled those days: “I listened eagerly even then to these things [said by Polycarp] … and made notes of them, not on paper but in my heart, and ever by the grace of God do I truly ruminate on them.”

St. Irenaeus felt a grave responsibility to carry forward Polycarp’s doctrine.

At some point, he moved from Smyrna to Lugdunum (Lyon in modern France). He was active in the life of the Church, which was then undergoing a renewed persecution under the Emperor Marcus Aurelius. Respected for his intelligence, and also for his connection to Polycarp, St. Irenaeus was consulted by popes on important questions of the day.

In the mid-second century, the Church suffered as much from division as from persecution. Christians in the East differed from those in the West about the proper day to celebrate the Lord’s resurrection. The argument grew so intense that there was danger of excommunication and schism. St. Irenaeus counseled moderation and calm, averting a crisis.

Still more damaging to the Church was a strain of heresy known as gnosticism. It was a movement of many sects, constantly metastasizing because its “revelation” came to individual teachers through private “knowledge” (in Greek, “gnosis”).

Gnostics held several characteristics in common. They believed that the true teaching of Jesus was not to be found in the words of the Gospels, but rather in “secrets” passed down through gnostic teachers. The secrets were not intended for many people, but only for a spiritual elite.

They also believed that the material world was an evil fabrication of a lesser god. Thus, they rejected the Old Testament with its stories of creation and its worship of the Creator.

Against the fanciful theories of the gnostics, St. Irenaeus contrasted the doctrine of the Catholic Church, which was public, simple, open to everyone, and could be traced directly to Jesus by a very short lineage. He recognized that lineage in the bishops who could legitimately claim to be successors of the apostles. His exemplary case is the line of bishops in Rome, the popes, whose names he can list off in entirety.

St. Irenaeus wrote many works, most of which have not survived into modern times. His masterpiece is “Against Heresies,” a five-volume refutation of gnosticism. But it is more than the negative critique suggested by its title. It is also a positive statement of the apostolic tradition, which St. Irenaeus called “the rule of faith.” 

Pope Benedict XVI, in 2007, credited Irenaeus with writing “the oldest catechism of Christian doctrine.”

In the course of this work he witnesses to both the humanity and divinity of Jesus. He speaks of the Trinity and Incarnation. He affirms the real presence of Jesus in the Eucharist. He demonstrates, moreover, that these teachings are consistent with the Scriptures and have been constant since the time of the apostles.

He also presents a developed Marian doctrine. He speaks of Mary as “undoing the knot of Eve’s disobedience,” thus laying the foundation for the modern devotion to the Blessed Virgin as “undoer of knots.”

St. Irenaeus won renown in his own lifetime and has been quoted as an authority in every generation afterward.

The time has come to recognize that authority in an official way, said Church historian Matthew Bunson. “The call for Pope Francis to declare St. Irenaeus of Lyon a doctor of the Church is arguably long overdue,” he told Angelus News. Bunson is co-author of the book “The 35 Doctors of the Church” (TAN Books, $28) and host of “The Doctors of the Church” on the Eternal Word Television Network.

But, he added, it’s also especially needed today. “In a time of neo-paganism, tragic amnesia of the beauty of Christianity, and the struggle to keep the young in the Faith, this great Father warns that we ‘should not seek among others the truth that can be easily gotten from the Church,’ but even more reminds us that only the Church ‘is the door of life.’ I add my prayer that the Holy Father will grant this plea from so many of the faithful.”