Other Writings.

        In addition to his major work, Irenaeus wrote a number of other books. Eusebius mentions one On Knowledge, “written against the Greeks,” as he says (Church History v. 26. 1). Jerome mistakenly thought this was two books (On Illustrious Men 35). Eusebius also mentioned a book dedicated to a certain brother named Marcianus, entitled In Demonstration ofthe Apostolic Preaching, and a “book of various dissertations.” This Demonstration, long lost, was discovered in 1904, at Eriwan, in Armenia, in an Armenian translation, and published with a German translation in 1907.[58] The book is a short one, of seventy-five or eighty pages, and was designed to give the intelligent Christian a summary of the Christian positions and the grounds for them. It gives new evidence of Irenaeus' debt to Justin Martyr but shows the advance Christian thought was making in the hands of men like Irenaeus.

        Irenaeus also wrote a number of letters that, to judge by their names, must have been almost treatises. Eusebius mentions one to Blastus On Schism, one On the Ogdoad, and one to Florinus On Sovereignty (Church History v. 20. 1). From this he quotes an important passage bearing on Polycarp, and on Irenaeus' memories of him (Church History v. 20. 2-8).

        Irenaeus himself says that he intends to write a book devoted to exposing the errors of Marcion (i. 27. 4.; iii. 12. 12), and Eusebius (Church History iv. 25) lists him among the writers against Marcion. The others he mentions are Philip of Gortyna and Modestus, and, of the three, he declares Modestus the most effective. But all these works on Marcion have disappeared.

        Irenaeus participated in the paschal controversy, so bitter in his day, between Polycrates and Ephesus and Victor of Rome. The important letter written by Polycrates to Victor on the subject is preserved in part in Church History v. 24. 2-8. Victor replied by excommunicating all the churches of Asia, which were represented by Polycrates. Irenaeus sought to calm the storm with a letter to Victor, pointing out that the East had long differed from the West in this matter, and yet the churches had respected and tolerated these differences of practice, and urging that they continue to do so. Parts of this wise and temperate letter are preserved in Eusebius (Church History v. 24. 12-I7). Eusebius adds that Irenaeus corresponded with most of the other Christian leaders of his day on this matter. He rightly held that Victor should not excommunicate whole churches of God.

        A few other fragments of Irenaeus have been discovered in later writers like John of Damascus, A.D. 675-749, but some of the fragments ascribed to him have been found to be modern forgeries, in particular those published in the middle of the eighteenth century by C. M. Pfaff (d. 1760).[59] It is evident that it would greatly serve the study of early Christian literature to find any one of the works of Irenaeus in the original Greek.