Hence, the act of faith by which I believe that the Son of God became man, that I shall rise from the dead, is first of all a _judgment of the reason_, not an act of the will, or a feeling of the heart. It is, moreover, a _certain_ rational judgment upon weighty reasons, not, indeed, such which I draw from intellectual knowledge, but those which rest upon the infallible testimony of God. The act of faith agrees therefore with assent to historic truth in that it is of the same kind of knowledge, but upon the authority of infallible testimony. Just as I believe that Alexander once marched victoriously through Asia, because there is sure testimony to that effect, so I believe that I shall rise from the dead, because God has revealed it. The difference being that in the former case we have only human testimony, whereas in the latter God Himself speaks. Thus, according to Catholic teaching, faith and knowledge may be distinct from each other, but in a sense quite different from that of the representatives of modern, sentimental faith. The latter understand knowledge, in this connection, to be any judgment of the reason based upon evidence, and they deny that faith is such; but to a Catholic, faith, too, is a _judgment of the reason_, and in this sense true knowledge; only it is not knowledge in the more common sense of a cognition derived from one’s own mental activity _without_ the external means of authority. As we have heard from the Vatican Council, it is the recognized fact of divine revelation which bestows upon the matter of faith its certainty in reason. Hence the knowledge of this fact must precede faith itself. But the knowledge must be certain, not merely a belief, for it is the very presupposition of belief, but a knowledge, derived from the intellect, which may at any time be traced back to scientific proofs if there is the requisite philosophical training. So long as man is not certain that God has spoken, he cannot have faith according to the Catholic view. One of the sentences condemned by _Innocent XI._, to say nothing of other ecclesiastical testimonies, is this: “The assent of supernatural faith, useful for salvation, can exist with merely probable information of the fact of revelation, even with the fear that God has not spoken.” And very recently there has been condemned also the proposition: “The assent of faith ultimately rests upon a sum of probabilities” (Decretum Lamentabile, July 3, 1907. Sent. 25). It cannot be our task here to show at length how the Christian arrives at this certain knowledge. Our present purpose is only to state the Catholic concept of faith. We have already heard the Vatican Council refer to miracles and prophecies. To most of the faithful the chief fact that offers them this security is the wonderful phenomenon of the _Catholic Church_ itself, which proposes to them the doctrines of faith as divine revelation.