John Calvin, Institutes of the Christian Religion, IV.8.5
First, if it is true, as Christ says, �Neither knoweth any man the Father save the Son, and he to whomsoever the Son will reveal him� (Matthew 11:27), then those who wish to attain to the knowledge of God behoved always to be directed by that eternal wisdom For how could they have comprehended the mysteries of God in their mind, or declared them to others, unless by the teaching of him, to whom alone the secrets of the Father are known? The only way, therefore, by which in ancient times holy men knew God, was by beholding him in the Son as in a mirror. When I say this, I mean that God never manifested himself to men by any other means than by his Son, that is, his own only wisdom, light, and truth. From this fountain Adam, Noah, Abraham, Isaac, Jacob, and others, drew all the heavenly doctrine which they possessed. From the same fountain all the prophets also drew all the heavenly oracles which they published.