The Scripture being a dead letter cannot explain or interpret itself.  Yet, since it is applied to the ever-varying lives of men, it needs an explanation and an interpretation; it is practically of no value without it.  And in order that the truth thus presented be accepted by men, it is necessary, of prime necessity, that it have the guarantee of infallibility.  This infallibility the Church of Christ possesses, else His mission were a failure.

This infallibility is to control the vagaries of Tradition, for Tradition, of its very nature, tends to exaggeration, as we find in the legends of ancient peoples.  Exaggerated, they destroy themselves, but in the bosom of God’s Church these truths forever retain their character unchanged and unchangeable.

If you accept the truth, the whole truth, and nothing but the truth as revealed by God and delivered to man by the infallible Church from the Bible and Tradition, you have what is called ecclesiastical, Catholic or true faith.  There is no other true faith.  It is even an open question whether there is any faith at all outside of this; for outside the Church there is no reasonable foundation for faith, and our faith must be reasonable.

However, granting that such a thing can be, the faith of him who takes and leaves off the divine Word is called divine faith.  He is supposed to ignore invincibly a portion of revealed truth, but he accepts what he knows.  If he knew something and refused to embrace it, he would have no faith at all.  The same is true of one who having once believed, believes no longer.  He impeaches the veracity of God, and therefore cannot further rely on His Word.

Lastly, it matters not at all what kind of truths we receive from God.  Truth is truth always and ever.  We may not be able to comprehend what is revealed to us, and little the wonder.  Our intelligence is not infinite, and God’s is.  Many things that men tell us we believe without understanding; God deserves our trust more than men.  Our incapacity for understanding all that faith teaches us proves one thing:  that there are limits to our powers, which may be surprising to some, but is nevertheless true.

CHAPTER XVIII.  WHY WE BELIEVE.

Belief, we have said, is the acceptance of a truth from another.  We do not always accept what others present to us as truth, for the good reason that we may have serious doubts as to whether they speak the truth or not.  It is for us to decide the question of our informant’s intellectual and moral trustworthiness.  If we do believe him, it is because we consider his veracity to be beyond question.

The foundation of our belief is therefore the veracity of him whose word we take.  They tell me that Lincoln was assassinated.  Personally, I know nothing about it.  But I do know that they who speak of it could know, did know, and could not lead us all astray on this point.  I accept their evidence; I believe on their word.