Saint Irenaeus of Lyons

detail of a stained glass window of Saint Irenaeus; 1901 by Lucien Bégule; Church of Saint Irenaeus, Lyon, France; photographed on 6 June 2010 by Gérald Gambier; swiped from Wikimedia CommonsAlso known as

  • Ireneo
  • Doctor unitatis
  • Doctor of Unity



Disciple of Saint Polycarp of Smyrna. Ordained in 177. Bishop of Lugdunum, Gaul (modern Lyons, France). Worked and wrote against Gnosticism, basing his arguments on the works of Saint John the Apostle, whose Gospel is often cited by Gnostics. Dispatched evangelists, including Saint Ferreolus of Besançon and Saint Ferrutio of Besançon. Considered the first great Western ecclesiastical writer and theologian, he emphasized the unity of the Old and New Testaments, and of Christ’s simultaneous human and divine nature, and the value of tradition. A Father of the Church. Martyr.






For this is why the Word became man, and the Son of God became the Son of man: so that man, by entering into communion with the Word and thus receiving divine sonship, might become a son of God. Saint Irenaeus

The Word Himself, born of Mary who was still a Virgin, rightly received in birth the recapitulation of Adam, thereby recapitulating Adam Himself. Saint Irenaeus, Against Heresies

The glory of God gives life; those who see God receive life. Men will therefore see God if they are to live; through the vision of God they become immortal and attain to God himself. God is the source of all activity throughout creation. He cannot be seen or described in his own nature and in all his greatness by any of his creatures. Yet he is certainly not unknown. Through his Word the whole creation learns that there is one God the Father, who holds all things together and gives them their being. As it is written in the Gospel, “No man has ever seen God, except the only-begotten Son, who is in the bosom of the Father; he has revealed him.” From the beginning the Son is the one who teacher us about the Father; he is with the Father from the beginning. The Word revealed God to men and presented men to God. Life in man is the glory of God; the life of man is the vision of God. If the revelation of God through creation gives life to all who live upon the earth, much more does the manifestation of the Father through the Word give life to those who see God. – from Against the Heresies by Saint Irenaeus

MLA Citation

  • “Saint Irenaeus of Lyons“. CatholicSaints.Info. 31 October 2021. Web. 26 January 2022. <>