Basil: Contra Eunomius 2.16

What sensible person would not agree that, just as an eye that passes out of clearly illuminated places must stop its activity because of the absence of light, so too the mind that is forced outside of true being by imaginations, as it the truth lacked a kind of light, becomes confused and stupid and desists from thinking? So, then, an eye is not able to use its power of sight when there is no light, and a soul led away from the notion of the Only-Begotten is not able to have use of its thinking. For falling away from the Truth makes the mind unable to see and blind. When the mind is empty and demented, it lacks true understanding and thinks that it comprehends things prior to the Only-Begotten. It is as if someone testifies that an eye starting at dark objects can see them clearly. For it says: in your light we shall see light (Ps. 35.10). But when Eunomius asserts that he has come to comprehend a point when the light did not yet exist, he resembles the delirious who imagine that they see what is not present. For one cannot conceive anything beyond the Son, since what is perceptible to light is to the eye, God the Word is to the soul. For it says: The true light that enlightens every human being was coming into the world (John 1.9). Hence the unenlightened soul is incapable of thinking. So, then, how could one comprehend that which is above the generation of light?

I think any with even a slight concern for the truth would dismiss corporeal comparisons, avoid sullying the notions about God with material imaginations, and follow the theological teachings transmitted to us by the Holy Spirit. Instead of posing these questions, which have no lack of conundrums, in which either of the options contains a risk, they should, on the one hand, conceive of a begetting that is worthy of God, one without passion, partition, division, and temporality, being led to the divine begetting in a way consistent with the radiance that shines forth from the light. They should, on the other hand, conceive of the image of the invisible God (Col. 1.15), not that which is produced later that the archetype like those images produced by human skill, but as that which is co-existent with and subsists alongside the one who brought him into subsistence. For the image exists by virtue of the fact that the archetype exists. The image is not formed through imitation, since the whole nature of the Father is manifest in the Son as in a seal. It may help you if we say that it is like a teacher inculcating the full reality of an art in his disciples: the teacher loses nothing, and the disciples attain the fullness of the art. But this example surely does not exhibit an exact resemblance because of the temporal interval. It is more suitable to say that it is like the nature of concepts that co-exist non-temporally with motions of the mind.