Certainly, then, He appealed to Reason; He appealed to Private Judgment, since that, up to that moment, was all that His hearers possessed. But, in demanding an Act of Faith, He appealed to Private Judgment to set itself aside; He appealed to Reason as to whether it were not Reasonable to stand aside for the moment and let Faith take its place. And we know how His disciples responded. _Whom do you say that I am?... Thou art the Christ, the Son of the Living God._ At that instant, then, a new stage was begun. They had used their Reason and their Private Judgment, and, aided by His grace, had concluded that the next reasonable step was that of Faith. Up to that point they had observed, dissected, criticized, and analyzed His words; they had examined, that is, His credentials. And now it was Reason itself that urged them towards Faith, Reason that abdicated what had hitherto been, its right and its duty, that Faith might assume her proper place. Henceforth, then, their attitude must be a different one. Up to now they had used their Reason to examine His claim; now it was Faith, aided and urged by Reason, which accepted it. Yet even now Reason's work is not done, though its scope in future is changed. Reason no longer examines whether He be God; Faith has accepted it: yet Reason has to be as active as ever; for Reason now must begin with all its might the task of understanding His Revelation. Faith has given them, so to speak, casket after casket of jewels; every word that Jesus Christ henceforth speaks to them is a very mine of treasure, absolutely true since He is known to be a Divine Teacher Who has given it. And Reason now begins her new work, not of justifying Faith, but, so to say, of interpreting it; not of examining His claims, since these have been once for all accepted, but of examining, understanding, and assimilating all that He reveals. III. Turn now to Catholicism. It is the Catholic Church, and the Catholic Church only, that acts as did Jesus Christ and offers an adequate object to Reason and Faith alike. For, first, it is evident that if Christ intended His Revelation to last through all time, He must have designed a means by which it should last, an Authority that should declare and preserve it as He Himself delivered it. And next, it is evident that since the Catholic Church alone even claims that prerogative, clearly and coherently, her right to represent that Authority is in proportion to the clearness and coherence of her claim. Or, again, she advances in support of that claim precisely those same credentials as did He: she points to her miracles, her achievements, the fulfilment of prophecy, the unity of her teaching, the appeal to men's moral sense--all of them appeals to Reason, and appeals which lead up, as did His, to the supreme claim, which He also made, to demand an Act of Faith in herself as a Divine Teacher.