Summary: Irenaeus was a Greek bishop noted for his role in guiding and expanding Christian communities in southern France and for the development of Christian theology by combating heresy and defining orthodoxy.

• Irenaeus c. 130 – c. 202 AD) was a Greek bishop noted for his role in guiding and expanding Christian communities in the southern regions of present-day France and, more widely, for the development of Christian theology by combating heresy and defining orthodoxy (conformity, agreement, conformation, conventionality). Originating from Smyrna, he had seen and heard the preaching of Polycarp, who in turn was said to have heard John the Evangelist, and thus was the last-known living connection with the Apostles.

Chosen as bishop of Lugdunum, now Lyon, his best-known work is Against Heresies, often cited as Adversus Haereses, a refutation of Gnosticism, particularly that of Valentinus. To counter the doctrines of the gnostic sects claiming secret wisdom, he offered three pillars of orthodoxy: the scriptures, the tradition handed down from the apostles, and the teaching of the apostles' successors. Intrinsic to his writing is that the surest source of Christian guidance is the Church of Rome. He is the earliest surviving witness to regard all four of the now-canonical gospels as essential.

He is recognized as a saint in the Catholic Church, which celebrates his feast on 28 June, and in the Eastern Orthodox Churches, which celebrates the feast on 23 August. Irenaeus is remembered in the Church of England with a Lesser Festival on 28 June. Pope Francis declared Irenaeus the 37th Doctor on 21 January 2022.

Personnel Details

Predecessor Pothinus

Successor Zechariah

Ordination by Polycarp

Born c. 130 AD Smyrna in Asia Minor Modern Day Izmir, Turkey

Influences Clement, Ignatius, Justin Martyr, Papias, Polycarp, The Shepherd of

Hermas

Influenced Agapius, Basil the Great, Epiphanius, Hippolytus, Tertullian

Irenaeus was a Greek from Polycarp's hometown of Smyrna in Asia Minor, now Izmir, Turkey, born during the first half of the 2nd century. The exact date is thought to be between the years 120 and 140. Unlike many of his contemporaries, he was brought up in a Christian family rather than converting as an adult.

During the persecution of Christians by Marcus Aurelius, the Roman emperor from 161 to 180, Irenaeus was a priest of the Church of Lyon. The clergy of that city, many of whom were suffering imprisonment for the faith, sent him in 177 to Rome with a letter to Pope Eleutherius concerning the heresy of Montanism. That occasion bore emphatic testimony to his merits. While Irenaeus was in Rome, persecution took place in Lyon. Returning to Gaul, Irenaeus succeeded the martyr Saint Pothinus and became the second bishop of Lyon.

During the religious peace that followed Marcus Aurelius's persecution, the new bishop divided his activities between the duties of a pastor and a missionary (as to which we have but brief data, late and not very sure). Almost all his writings were directed against Gnosticism. The most famous of these writings is Adversus haereses (Against Heresies). Irenaeus alludes to coming across Gnostic writings and holding conversations with Gnostics, which may have taken place in Asia Minor or Rome. However, it also appears that Gnosticism was present near Lyon: he writes that there were followers of 'Marcus the Magician' living and teaching in the Rhone valley.

Little is known about the career of Irenaeus after he became bishop. The last action reported of him (by Eusebius, 150 years later) is that in 190 or 191, he influenced Pope Victor I not to excommunicate the Christian communities of Asia Minor, which persevered in the practice of the Quartodeciman celebration of Easter.

Nothing is known of the date of his death, which must have occurred at the end of the second or the beginning of the third century. He is regarded as a martyr by the Catholic Church and some within the Orthodox Church. He was buried under the Church of Saint John in Lyon, which was later renamed St Irenaeus in his honor. The tomb and its remains were utterly destroyed in 1562 by the Huguenots.

Writings

Irenaeus wrote several books, but the most important that survives is the Against Heresies (or, in its Latin title, Adversus haereses). In Book I, Irenaeus talks about the Valentinian Gnostics and their predecessors, whom he says to go as far back as the magician Simon Magus. In Book II, he attempts to provide proof that Valentinianism contains no merit in terms of its doctrines. In Book III, Irenaeus purports to show that these doctrines are false by providing counter-evidence gleaned from the Gospels. Book IV consists of Jesus's sayings, and here Irenaeus also stresses the unity of the Old Testament and the Gospel. In the final volume, Book V, Irenaeus focuses on more sayings of Jesus plus the letters of Paul the Apostle.

Irenaeus wrote: "One should not seek among others the truth that can be easily gotten from the Church. For in her, as in a rich treasury, the apostles have placed all that pertains to the truth so that everyone can drink this beverage of life. She is the door of life." However, he also said, "Christ came not only for those who believed from the time of Tiberius Caesar, nor did the Father provide only for those who are now, but for absolutely all men from the beginning, who, according to their ability, feared and loved God and lived justly. . . and desired to see Christ and to hear His voice Irenaeus recognized that all who feared and loved God, practiced justice and piety towards their neighbors, and desired to see Christ, insofar as they were able to do so, will be saved. Since many were not able to have an explicit desire to see Christ, but only implicit, it is clear that for Irenaeus, this is enough.

The purpose of "Against Heresies" was to refute the teachings of various Gnostic groups; apparently, several Greek merchants had begun an oratorial campaign in Irenaeus's bishopric, teaching that the material world was the accidental creation of an evil god, from which we are to escape by the pursuit of gnosis. Irenaeus argued that the true gnosis is knowledge of Christ, which redeems rather than escapes from bodily existence.

Until discovering the Library of Nag Hammadi in 1945, Against Heresies was the best surviving description of Gnosticism. Some religious scholars have argued that the findings at Nag Hammadi have shown Irenaeus's description of Gnosticism to be inaccurate and controversial. However, the consensus among modern scholars is that Irenaeus was reasonably accurate in his transmission of gnostic beliefs and that the Nag Hammadi texts have raised no substantial challenges to the overall accuracy of Irenaeus's information. For example, religious historian Elaine Pagels criticizes Irenaeus for describing Gnostic groups as sexual libertines, example, when some of their writings advocated chastity more strongly than orthodox texts. However, the Nag Hammadi texts do not present a single, coherent picture of any unified gnostic belief system but somewhat divergent beliefs of multiple Gnostic sects. Some of these sects were indeed libertine because they considered bodily existence meaningless; others praised chastity and prohibited sexual activity, even within marriage.

Irenaeus also wrote The Demonstration of the Apostolic Preaching (also known as Proof of the Apostolic Preaching), an Armenian copy of which was discovered in 1904. This work seems to have been an instruction for recent Christian converts.

Eusebius attests to other works by Irenaeus, today lost, including On the Ogdoad, an anonymous letter to Blastus regarding schism, On the Subject of Knowledge, On the Monarchy or How God is not the Cause of Evil, On Easter.

Irenaeus exercised a vast influence on the generation which followed. Both Hippolytus and Tertullian freely drew on their writings. However, none of his works aside from Against Heresies and The Demonstration of the Apostolic Preaching survive today, perhaps because his literal hope of an earthly millennium may have made him unpleasant reading in the Greek East. Even though no complete version of Against Heresies in its original Greek exists, we possess the full ancient Latin version, probably of the third century, thirty-three fragments of a Syrian version, and a complete Armenian version of books 4 and 5.

Irenaeus's works were first translated into English by John Keble and published in 1872 as part of the Library of the Fathers series.

Scripture

Irenaeus pointed to the public rule of faith, authoritatively articulated by bishops' preaching and taught in Church practice, especially worship, as an authentic apostolic tradition to read Scripture honestly against heresies. He classified as Scripture not only the Old Testament but most of the books now known as the New Testament while excluding many works, a large number by Gnostics, that flourished in the 2nd century and claimed scriptural authority. Frequently, as a student of Polycarp, who was a direct disciple of the Apostle John, Irenaeus believed that he was interpreting scriptures in the same hermeneutic (a method or principle of interpretation) as the Apostles. This connection to Jesus was essential to Irenaeus because he and the Gnostics based their arguments on Scripture. Irenaeus argued that since he could trace his authority to Jesus and the Gnostics could not, his interpretation of Scripture was correct. He also used "the Rule of Faith," a "proto-creed" with similarities to the Apostles' Creed, as a key to arguing that his interpretation of Scripture was correct.