St. Irenaeus of Lyons


Catholic priest and bishop in France, active from about 170 A.D. to 180 A.D. One of the Church Fathers.

Early childhood. “I also saw [St. Polycarp] in my early youth, for he tarried [on earth] a very long time.” (Irenaeus, Against Heresies Book 3 Chapter 3)

“I remember the events of that time more clearly than those of recent years. For what boys learn, growing with their mind, becomes joined with it; so that I am able to describe the very place in which the blessed Polycarp sat as he discoursed…” (Eusebius, Church History Book 5 Chapter 20)

“[His teachings were] told me by the mercy of God, [and] I listened to them attentively, noting them down, not on paper, but in my heart. And continually, through God's grace, I recall them faithfully.” (ibid.)

Ambassador to the pope. “Irenæus...was already at that time a presbyter of the parish of Lyons.” “[The martyrs of Lyons] recommended Irenæus...to the above-mentioned bishop of Rome, saying many favorable things in regard to him.” (Eusebius of Caesarea’s Church History Book 5 Chapter 4)

“Irenæus…[sent] letters [to the pope] in the name of the brethren in Gaul over whom he presided, [and] maintained that the mystery of the resurrection of the Lord should be observed only on the Lord's day. [But he] fittingly admonishes [Pope] Victor that he should not cut off whole churches of God [for] observ[ing] the tradition of an ancient custom. …  Irenæus...became a peacemaker in this matter, exhorting and negotiating in this way in behalf of the peace of the churches. And he conferred by letter...not only with Victor, but also with most of the other rulers of the churches.” (Eusebius of Caesarea’s Church History Book 5 Chapter Chapter 24)

Dealings with heretics. “Irenæus wrote several letters against those who were disturbing the sound ordinance of the Church at Rome. One of them was to Blastus On Schism; another to Florinus On Monarchy, or That God is not the Author of Evil. For Florinus seemed to be defending this opinion. ... Irenæus [also wrote] the work which comprises five books [against Gnosticism]...[and the book] Demonstration of the Apostolic Preaching.” (Eusebius of Caesarea’s Church History Book 5 Chapters 20, 7, 26)

Catholic Apologetics