One, Immaterial, Incomprehensible; Revealed in Creation - and especially in Mind
Therefore, having refuted, to the best of our ability, every interpretation of Scripture which suggests that anything material is to be understood in God, we say that the true nature of God cannot be comprehended by our thought.
For if there is anything that we are able to conceive or understand about God, we are bound to believe him far superior to anything which we conceive. If we saw a man scarcely able to look at a spark of light … and we wished to teach him about the brightness and the splendour of the sun; should we not have to tell him 'The sun's splendour is better and grander all this light which you see, to a degree which cannot be described or imagined'?
So, while our mind is shut up within the confines of flesh and blood, and is rendered duller and blunter by its connexion with such material substances; though it be considered far superior to material nature, nevertheless, when it strives towards the immaterial, then it scarcely attains the standing of a spark …
Our eyes cannot behold the very nature of light, that is, the sun's own self: but beholding it's brightness, or its rays … we can consider how great is the source and origin of material light. Now the works of the divine providence and the design of the whole universe are as it were rays of God's nature, in comparison with his very being.
Our mind cannot behold God as he is in himself, therefore it forms its conception of the Creator of the universe from the beauty of his works and the loveliness of his creatures…. God is to be thought of as an uncompounded, intellectual being … a monad and, so to say, a unit, a mind, and the source from whom is the beginning of all intellectual being or mind … ..
…. There is a kinship between the human mind and God; for the mind is itself an image of God, and therefore can have some conception of the divine nature, especially the more it is purified and removed from matter.
The Early Christian Fathers