(pronounced ear-a-NAY-us) was probably born around 125. As a young man in Smyrna (near Ephesus, in what is now western Turkey) he heard the preaching of Polycarp, who as a young man had heard the preaching of the Apostle John. Afterward, probably while still a young man, Polycarp moved west to Lyons in southern France. In 177, Pothinus, the bishop of Lyons, sent him on a mission to Rome. During his absence a severe persecution broke out in Lyons, claiming the lives of the bishop and others. When Irenaeus returned to Lyons, he was made bishop. He died around 202. He is thus an important link between the apostolic church and later times, and also an important link between Eastern and Western Christianity.
During the persecution of Marcus Aurelius, the Roman Emperor from 161-180, 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 or 178) to Rome with a letter to Pope Eleuterus concerning the heresy Montanism, and that occasion bore emphatic testimony to his merits. Returning to Gaul, Irenaeus succeeded the martyr Saint Pothinus and became the second Bishop of Lyon.
During the religious peace which followed the persecution of Marcus Aurelius, the new bishop divided his activities between the duties of a pastor and of a missionary (as to which we have but brief data, late and not very certain). Almost all his writings were directed against Gnosticism. The most famous of these writings is Adversus haereses (Against Heresies). In 190 or 191, he interceded with Pope Victor I to lift the sentence of excommunication laid by that pontiff upon 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. In spite of some isolated and later testimony to that effect, it is not very probable that he ended his career with martyrdom. He was buried under the Church of Saint John in Lyons, which was later renamed St Irenaeus in his honour.
Irenaeus - 28 June - Bishop of Lyons, Theologian, and Church Father
ALMIGHTY God, who didst uphold thy servant Irenaeus with strength to maintain the truth against every wind of vain doctrine: We beseech thee to keep us steadfast in thy true religion, that we may walk in constancy and in peace the way that leadeth to eternal life; through Jesus Christ our Lord. Amen.
The Epistle - Malachi 2:5-7.
MY covenant was with him of life and peace; and I gave them to him for the fear wherewith he feared me, and was afraid before my name. The law of truth was in his mouth, and iniquity was not found in his lips: he walked with me in peace and equity, and did turn many away from iniquity. For the priest's lips should keep knowledge, and they should seek the law at his mouth: for he is the messenger of the Lord of hosts.
The Gospel - St. Luke 11:33-36.
NO man, when he hath lighted a candle, putteth it in a secret place, neither under a bushel, but on a candlestick, that they which come in may see the light. The light of the body is the eye: therefore when thine eye is single, thy whole body also is full of light; but when thine eye is evil, thy body also is full of darkness. Take heed therefore that the light which is in thee be not darkness. If thy whole body therefore be full of light, having no part dark, the whole shall be full of light, as when the bright shining of a candle doth give thee light.
References and Resources: