the Church is the fact of her being the depository of the truth, he was no longer able to confine himself to this (see above). The episcopal succession and the transmission to the bishops of the _magisterium_ of the Apostles were not indeed of any direct importance to his idea of the Church, but they were of consequence for the preservation of truth and therefore indirectly for the idea of the Church also. To Irenaeus, however, that theory was still nothing more than an artificial line; but artificial lines are really supports and must therefore soon attain the value of foundations.[153] Tertullian's conception of the Church was essentially the same as that of Irenaeus; but with the former the idea that she is the outward manifestation of the Spirit, and therefore a communion of those who are spiritual, at all times continued to operate more powerfully than with the latter. In the last period of his life Tertullian emphasised this theory so vigorously that the Antignostic idea of the Church being based on the "traditio unius sacramenti" fell into the background. Consequently we find nothing more than traces of the hierarchical conception of the Church in Tertullian. But towards the end of his life he found himself face to face with a _fully developed_ theory of this kind. This he most decidedly rejected, and, in doing so, advanced to such a conception of ecclesiastical orders, and therefore also of the episcopate, as clearly involved him in a contradiction of the other theory--which he also never gave up--viz., that the bishops, as the class which transmits the rule of faith, are an apostolic institution and therefore necessary to the Church[154].