under the then generally accepted forms of philosophical speculation, and to commend it as a manifestation of the highest reason to the cultured minds of his time. In this way he became the first founder of a Catholic system of theology. The doctrine of the Divine Logos as the "Second God," the Mediator through Whom all divine revelation is transmitted, was already for Justin an apologetic weapon, remained thence forward a standing basis for the philosophical defence of Christianity, and proved in after-times the strongest weapon in the church's armoury in the conflict with Gnostic opinions.
The widespread appearance of the manifold forms of Gnosticism in the 2nd cent. is a most significant proof of the far-reaching influence exercised by pagan thought and speculation on the Gentile church of that age. The danger from the influx on all sides of foreign thought was all the greater because the Gentile churches had as yet but a feeble comprehension of the ideas specially belonging to Christianity. The conflict with Gnosticism gradually gave fresh vigour to that revival of fundamental Christian and Pauline thought which distinguishes the theology of Irenaeus and of other early "Catholic" doctors at the end of the 2nd and beginning of the 3rd cent. from the simpler and poorer view of Christian truth presented in the works of the early Apologists. The perils with which the Gnostic speculation menaced the Christian system were, on the one hand, concerned with that which formed a common groundwork for Christianity and Judaism—i.e. first and specially the Monotheistic principle itself, and then the doctrines of Divine Justice, Freedom of the Will, and Future Retribution; on the other hand, they had regard to the traditions peculiar to Christianity concerning the historical person and work of Jesus Christ, the genuine human realism of His life and sufferings, the universal application of His redeeming work to all believers, and the external and historical character of that final restitution to which Christians looked forward. The Monotheistic idea, the divine μοναρχία, was assailed by the Gnostic doctrine of the Demiurge, the Pleroma, and the series of Aeons; and the universally accepted doctrine of our Lord's Incarnation and Messiahship by the various forms of Gnostic docetism. Further, the whole ethical basis of Christian religion was destroyed by the distinctions which Gnostic teachers made between two or three separate classes of mankind, and by their view of redemption as a purely theoretical process, or as the impartation of true knowledge (gnosis) to those only who by their own originally pneumatic nature had from the beginning been predestined to reception into the heavenly realm of light. Instead of the Christian doctrine of Freewill and consequent responsibility, they taught an iron heathenish metaphysical Necessity, which arbitrarily determined the fortunes of men; instead of a future divine recompense according to the measure of faith and works, a one-sided over-estimation of mere knowledge as the one condition of ultimate salvation; instead of the original Christian notion of the final consummation as a series of great outward visible occurrences, the resurrection of the flesh, a day of final judgment, and the setting up on earth of a millennial kingdom, they taught the spiritualistic conception of a saving deliverance of pneumatic souls and their translation into the upper world; whereas for the Psychici was reserved only a limited share in such knowledge and salvation, and for the material ("hylic" or "choic") man and for the earthly bodies of men, nothing but an ultimate and complete annihilation. It cannot be denied that both the Gentile Christianity of that era and the Catholic theology of following times appropriated various elements nearly related to these Gnostic speculations. A Catholic gnosis also appeared, which differed essentially from that heretical gnosis in intending to maintain unimpaired the received foundations of Christian faith. Yet, in truth, the idealistic speculations of the Alexandrine school were separated from those of the heretical gnosis by very uncertain lines of demarcation, and were afterwards, in some essential points, rejected by the church. Irenaeus, in contradistinction to the Alexandrine doctors, appears to have been less concerned with setting up a Catholic in opposition to the heretical gnosis, than with securing the foundations of the common Christian faith by strengthening the bands of existing church unity. He recognizes certain subjects which, as lying outside the rule of faith delivered to all, might be safely entrusted to the deeper and more searching meditations and inquiries of the more enlightened, but these related only to a clearer understanding of the details of the history of divine revelation, the right interpretation of parables, insight into the divine plan of human salvation (why God should bear with such long-suffering the apostasy of angels and the disobedience of man at the Fall), the differences and unity of the two Testaments, the necessity for the Incarnation of the Logos, the second coming of Christ at the end of time, the conversion of the heathen, the resurrection of the body, etc. (Haer. i. 10, 3). These questions would arise in the course of the Gnostic controversy, but the form in which Irenaeus presents them assumes everywhere a clear antithesis to Gnostic speculation and a firm retention of the Catholic rule of faith. Only in quite an isolated form is once named the question why one and the same God should have created the temporal and the eternal, the earthly and the heavenly; while Irenaeus insists strongly on the narrow bounds of human knowledge and insight, and on the impossibility for mortal man to know the reasons for everything (ii. 25, 3; 28, 1), and is never weary of chastising the arrogant presumption of the Pneumatici who exalt themselves above the Creator, while their impotence in the presence of His works is manifest to all (ii. 30, 1 sqq.).
His theoretical refutation of Gnostc opinions, e.g. in bk. ii., is full of acute remarks. His main purpose is to repel the Gnostic assault on the divine monarchia. He shews that by the separation of the Creator from the highest God, the absolute being of God Himself is denied. Neither above nor beside the Creator Himself can there be any other principle, for so God Himself would cease to be the
