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  • Five Books of S. Irenaeus, Bishop of Lyons, Against Heresies, translated by John Keble, with the Fragments that Remain of His Other Works (Oxford, London: James Parker & Co.; London, Oxford, Cambridge: Rivingtons, 1872). With a Preface by P.E. Pusey. Volume 42 of A Library of the Fathers of the Holy Catholic Church, Anterior to the Division of the East and the West, translated by Members of the English Church. May be read online, and available in multiple formats (pdf, epub, text, kindle/mobi, etc.), at Internet Archive and Open Library, with a 2nd copy at Internet Archive, and 3rd (incomplete) copy, which begins only on page 6, at Internet Archive. May be read online, and available in PDF format, at Hathi Trust Digital Library.
  • N.B.:
    • St. Irenaeus’s opus (written around 180 A.D.) was intended as a comprehensive apologia for authentic or Catholic Christianity against Gnosticism. Considering that he was a student of St. Polycarp, who was a student of St. John the Apostle, St. Irenaeus’s work strongly evidences the continuity of Catholic teaching (including on the sacraments, the Roman primacy, the apostolic succession of the bishops, sacred tradition, etc.) since Apostolic times.
    • Readers are generally advised to focus on Book III and IV, which provide an eminently readable summary of Christian teaching. They may choose to omit, absent need or preparation, the detailed summary and refutation of Gnostic errors contained in Books I and II, and the eschatological speculations contained in Book V.
    • This text is also available at Forgotten Books, whose freely downloadable pdf text has some pages missing (and replaced with a truly tacky poster for non-members).
    • This translation was made by a non-Catholic, albeit by a pioneer of the Oxford Movement that led so many to the one true Church. However, unlike the translation contained in Philip Schaff’s otherwise excellent Ante-Nicene Fathers series, it does not appear to have the anti-Catholic preface and footnotes inserted by the editor thereof. (The Schaff text is reproduced without footnotes in the New Advent online edition.)

On the Feast of St. Irenaeus of Lyons in the Ordinary Form of the Roman Rite. For other legally free ebooks, you may access the List of Free eBooks (Arranged by Title) and the List of Free eBooks (Grouped by Subject).

O God, our refuge and our strength, look down with mercy upon the people who cry to Thee; and by the intercession of the glorious and immaculate Virgin Mary, Mother of God, of Saint Joseph her spouse, of the blessed Apostles Peter and Paul, and of all the saints, in Thy mercy and goodness hear our prayers for the conversion of sinners, and for the liberty and exaltation of the Holy Mother the Church. Through the same Christ Our Lord. Amen. (From Sancta Missa)