That is true, if God failed to do so. But He did not. Your reason tells you that Christianity teaches certain mysterious things. You ask on what authority it so teaches. You are told that Almighty God has revealed those doctrines. At once the fact that the doctrines are extraordinary becomes of no account. God must know, and is certainly supremely truthful. The only point is, did He reveal such doctrines. You are shown that they are contained in the Bible, and that the Catholic Church teaches them. Your duty is to make sure that the Bible is a reliable source of such information, and that the Catholic Church is an institution guaranteed by God as a safe and authentic teacher of men in religious matters. If these things have been reasonably verified, as they certainly can be, you reasonably and freely accept the doctrines thus guaranteed as being of God. Now God has not failed to endow you with sufficient reason to do this. If you refuse to use your reason, or if you misuse it, or if you refuse to believe all that you do not fully comprehend for yourself, despite your knowledge that God has revealed such doctrines, you are to blame. Remember that to refuse to believe because reason does not entirely comprehend a doctrine, is to say that human reason is the ultimate test of all truth. That is not true which human reason cannot demonstrate to its own satisfaction! In the light of the obvious limitation of human reason, and the history of human aberrations in thought, this is clearly an irrational position. The conclusion remains that Christ justified His claims to be the divinely sent Teacher of men; that He sent His Apostles and their legitimate successors to teach all nations; that He thereby laid upon all nations the obligation of being taught; and that, once His teaching has been sufficiently put before them, men are guilty if they presume to reject it. In the case of such men, acceptance of the Christian religion is necessary if they are to be saved.
Radio Replies Volume 1 by Rev. Dr. Leslie Rumble MSC and Rev. Charles Mortimer Carty