Irenaeus (c130-c202) was an early Father of the Church who confronted the threat presented to Christianity by the Gnostics.
Gnosticism flourished before the birth of Christ, and in some aspects persists today. The phenomenon, however, has always been so diffuse that it is difficult to define.
The heresy’s starting-point is that this world is too fundamentally flawed to be the creation of a perfect God. Rather, the Gnostics speculated, it was the work of the Demiurge, a partially corrupted emanation from the supreme deity. The ultimate divinity remains hidden from mankind. Even so, buried deep within us, there are inklings of its existence, discernible by those inherently gifted with spiritual insight, or possessed of the appropriate secret formulae.
For the Gnostics, then, religious knowledge was confined to the superior intellect. To such sophisticates there could be no absolute truth or morality, merely intuitions gathered by the favoured few. As for Christ, while He might be regarded as a valued teacher, he could hardly be part of the Godhead.
Irenaeus perfectly captured the smugness that Gnosticism imbued: “As soon as a man has been won over to their way of salvation, he becomes so puffed up with conceit and self-importance that he imagines himself to be no longer in heaven or on earth, but to have already passed into the fullness of God’s powers.
“With the majestic air of a cock he goes strutting about, as if he had already embraced his angel.”
Irenaeus carried especial authority because he was associated with the very roots of Christianity. Apparently born in the eastern Mediterranean, he had been taught by a disciple of St John, Polycarp of Smyrna, who relayed to him the Apostles’ accounts of conversations with Jesus.
Somehow Irenaeus became a priest in Lyon. Perhaps he earned his irenical, “peace-giving”, name in 177 when he was dispatched to Rome to urge Pope Eleutherius to adopt a more lenient policy towards an over-enthusiastic sect of Montanists in Phrygia.
On his return to Lyon, he was appointed bishop in place of St Pothinus, who had been martyred at the age of 90.
While some Gnostics gained a reputation for asceticism, Irenaeus railed against their sexual licence. What else, he demanded, could be expected of those who believed that “conduct is only good or evil in the eyes of man”? Irenaeus insisted that sinful men and women required a religious authority above and beyond their individual whims. Christian practice and morality, he taught, was laid down in apostolic tradition and Scripture. But which Scripture exactly? Irenaeus played an important part in rejecting various Gnostic texts and establishing the canon of the four gospels, later confirmed by Church councils.
Irenaeus died in Lyon, where his shrine survived until destroyed by the Calvinists in 1562.