Irenaeus of Lyon
c. 130 – 202 · Gaul
“...that ye should earnestly contend for the faith which was once delivered unto the saints.”
A student of Polycarp, who himself had known the apostle John, Irenaeus became bishop of Lyon in Roman Gaul. His massive work Against Heresies systematically refuted Gnostic teachings, appealing to a chain of apostolic teaching he could trace back through only two links.
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