These, then, were the two modes in which the Christian Faith pursued and attained its orderly increase; as a seed it grew to a plant in each city, and as a plant it ramified, or as Tertullian says, carried "the vine-layer of the faith"(216) from city to city, from province to province. In the meantime the last disciples of the Apostles, those who from the especial veneration with which they were regarded as teachers of the Faith and "second links in the chain of tradition," were termed Presbyters,(217) had died out. S. Polycarp, at the time of his martyrdom in 167, was probably the sole remaining one, though his pupil S. Irenæus had known others. When the latter, upon the martyrdom of S. Pothinus in 177, is raised to the government of the See of Lyons, we may consider that no one survived in possession of that great personal authority which belonged to those who had themselves been taught by Apostles; and so at the third generation from the last of these the Church throughout the world stood without any such support, simply upon that basis of the tradition and teaching of the truth, and of the succession of rulers, on which the Apostles had placed it, to last for ever. Now in this position it had already, throughout the whole course of the second century, been violently assaulted by a family of heresies, which growing upon one root--a natural philosophy confusing the being of God with the world--burst forth into an astonishing variety of outward forms. Gnosticism completely altered and defaced Christian doctrine under each of the four great heads, the Being of God, the Person of Christ, the nature of man, the office and function of the Church. Into the Godhead it introduced a dualism, recognising with the absolute good an absolute evil represented by matter: it denied the reality of the Incarnation; it made the body a principle of evil in man's nature: but we will here limit ourselves to the characteristic and formal principle of the system from which it derived its name, to Gnosis as the means of acquiring divine truth. Now the Christian religion taught that revealed truth was to be attained by the individual through receiving, upon the ground of the divine veracity, those mysterious doctrines superior but not contrary to reason which it unfolded; and that the communication of such doctrines might continue unimpaired and unchanging, it taught that our Lord had established a never-failing authority charged with the execution of this office, and assisted by the perpetual presence of His Spirit with it to the end. But the Gnostics admitted only in the case of the imperfect or natural man that faith was the means for acquiring religious truth; to the spiritual, the proper gnostic, gnosis should take the place of faith: for to many a heathen, accustomed to unlimited philosophical speculation, the absolute subjection of the intellect to divine authority, required by the principle of faith, was repugnant. Now this Gnosis was in their mind not knowledge grounded upon faith, but either philosophic science, or a supposed intuition of truth, which was not only to replace faith, but the whole moral life, inasmuch as the completion and sanctification of man were to be wrought by it. And thus instead of an external authority the individual reason was set up as the highest standard of religious truth, the issue of which could only be rationalism in belief and sectarianism in practice.