Irenaeus was lived approximately 130-200. He was bishop of Lyons. Growing up in Smyrna under Polycarp, Irenaeus studied in Rome in the school of Justin Martyr (ca. 100 - ca. 165). Sometime after 164 he moved to Lyons, where he was ordained a presbyter.
He narrowly missed martyrdom in 177 when the aged bishop of Lyons, Pothinus, dispatched him to Rome with a letter for Pope Eleutherius (175-89). While he was away, Pothinus and other church leaders in Lyons were arrested and executed. When Irenaeus returned he succeeded Pothinus as bishop.
We know little of Irenaeus's activities as a bishop, but two of his major writings have survived -- Refutation and Overthrow of Knowledge Falsely So-Called (usually referred to as Against Heresies) and Proof of the Apostolic Preaching, a manual for use by someone trying to win inquirers to the Christian faith. ... Irenaeus contended that Jesus lived to age fifty on the basis of John 8:57, passing through every stage of human life. He also laid a base for the Eastern Christian concept of deification with the remark that Jesus became human in order that we might become divine. His statement that all churches must agree with the Church of Rome on account of its greater antiquity or more powerful authority has occasioned much debate among Protestant, Catholic, and Orthodox scholars.
[Excerpted with permission from the entry on Irenaeus by E. Glenn Hinson, from The Upper Room Dictionary of Christian Spiritual Formation, edited by Keith Beasley-Topliffe. Copyright © 2003 by Upper Room Books®. All rights reserved.]
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