On Knowing God | St. Gregory Nazienzen. Oration 28.4-6
So we must begin again with this in mind. To know God is hard, to describe him impossible, as a pagan philosopher taught— subtly suggesting, I think, by the word “difficult” his own apprehension, yet avoiding our test of it by claiming it was impossible to describe. No—to tell of God is not possible, so my argument runs, but to know him is even less possible. For language may show the known if not adequately, at least faintly, to a person not totally deaf and dull of mind. But mentally to grasp so great a matter is utterly beyond real possibility even so far as the very elevated and devout are concerned, never mind slack and sinking souls. This truth applies to every creature born, to all beings whose view of reality is blocked by this gloom, this gross portion of flesh. Whether higher, incorporeal natures can grasp it, I do not know. They may, perhaps, through their proximity to God and their illumination by light in its fullness know God if not with total clarity, at least more completely, more distinctly than we do, their degree of clarity varying proportionately with their rank.
But enough of this! For our part, not only does God’s peace pass all thought and understanding with all the things stored up in promise for the righteous— things unseen by the eye, unheard by the ear, unthought, or at least but glimpsed by the mind—but so does exact knowledge of the creation as well. You can be sure that we possess but the bare outline of the creation when you hear the words: “I shall see the heavens, the works of thy fingers, the Moon and the Stars” and the fixed order they contain. He does not see them now, but there is a time when he shall see them. Yes, far more than these things does their transcendent cause, the incomprehensible and boundless nature pass understanding. I mean understanding what that nature is, not understanding that it exists. Our preaching is not vain, our faith empty; it is not that doctrine we are propounding. Do not take our frankness as ground for atheistic caviling and exalt yourselves over against us for acknowledging our ignorance. Conviction, you see, of a thing’s existence is quite different from knowledge of what it is.
That God, the creative and sustaining cause of all, exists, sight and instinctive law inform us—sight, which lights upon things seen as nobly fixed in their courses, borne along in, so to say, motionless movement; instinctive law, which infers their author through the things seen in their orderliness. How could this universe have had foundation or constitution, unless God gave all things being and sustains them? No one seeing a beautifully elaborated lyre with its harmonious, orderly arrangement, and hearing the lyre’s music will fail to form a notion of its craftsman-player, to recur to him in thought though ignorant of him by sight. In this way the creative power, which moves and safeguards its objects, is clear to us, though it be not grasped by the understanding. Anyone who refuses to progress this far in following instinctive proofs must be very wanting in judgment. But still, whatever we imagined or figured to ourselves or reason delineated is not the reality of God. If anyone ever did compass this in any degree of thought, where is the proof? Who was it who reached this ultimate in wisdom? Who was it who was sometime counted worthy of so great a gift? Who was it who thus opened his mind’s mouth and drew in the Spirit, that by the Spirit which searches out and knows God’s depths he might comprehend God, might stand in no need of further progress as owning already the ultimate object of desire towards which speeds all a lofty soul’s thought and conduct?