Roman Catechism 3.9

Chapter 3 — Part I: The Creed — Article I: I Believe in God, the Father Almighty, Creator of Heaven and Earth

Section 9. Justly, therefore, do the faithful profess first to believe in God, whose majesty, with the Prophet Jeremias, we declare incomprehensible. For, as the Apostle says, He dwells in light inaccessible, which no man hath seen, nor can see; as God Himself, speaking to Moses, said: No man shall see my face and live. The mind cannot rise to the contemplation of the Deity, whom nothing approaches in sublimity, unless it be entirely disengaged from the senses, and of this in the present life we art naturally incapable.