Irenaeus, born around 130 to a Christian family, was a disciple of Bishop Polycarp in Smyrna, who had himself been a disciple of the Apostle John.  After a persecution decimated the church in Gaul, Irenaeus became the second bishop of Lyon and was noted for his role in guiding and expanding Christian communities in what is now the south of France.  In his treatise Against Heresies, Irenaeus exposed the errors of Gnostic heresy and was instrumental in defining apostolic orthodoxy as one of the first systematic Christian theologians.

God's splendor is the source of life; those who see him share his life.  Because he was beyond the reach of man's mind, incomprehensible and invisible, he made himself visible, intelligible and knowable so that those who see and accept him may possess life.