Before he can see, man must have both sight and light. Eyes cannot see in the darkness, and light shows nothing to the blind. So with regard to the Truth: there must be the seeing eye and illuminating light. For an interpreter we need a trustworthy guide, an infallible teacher; and he is to be found not in the "Church," the "voice of tradition," the "intuitive faculty," or in reason, but in the Spirit of God. He it is who quickens, illumines, interprets, and the only instrument which He uses is the written Word. Therefore is He called "the Spirit of the truth."
