Chapter 105 — How the created intellect can see the divine essence

We must now consider how this is possible. Manifestly, since our intellect knows nothing except through an intelligible species of the thing known, the species of one thing cannot disclose the essence of another thing. The more distant the species through which the intellect knows is from the thing known, the less perfect knowledge our intellect has of that thing’s essence. For example, if we should know an ox by the species of an ass, we would have an imperfect knowledge of the essence of the ox: indeed, it would only be of the genus. Our knowledge would be still more defective if we were to know the ox through the medium of a stone, because then we would know it by a more remote genus. And if our knowledge were gained through the species of a thing that did not agree with the ox in any genus, we could not know the essence of the ox at all.

It is clear from the previous discussion that no creature shares a genus with God. Hence the essence of God cannot be known through any created species whatever, whether sensible or intelligible. Accordingly, if God is to be known as he is, in his essence, God himself must become the form of the intellect knowing him and must be joined to that intellect, not indeed so as to constitute a single nature with it, but in the way an intelligible species is joined to the intelligence. For God, who is his own being, is also his own truth, and truth is the form of the intellect.

Whatever receives a form must first acquire a disposition to that form. Our intellect does not by its very nature have the last disposition toward that form which is truth; otherwise it would be in possession of that truth from the beginning. Consequently, when it does attain to truth, it must be elevated by some disposition newly conferred on it. And this we call the light of glory, with which God fills our intellect, who alone by his very nature has this form properly as his own, even as heat, which is the disposition toward the form of fire, can come from fire alone. This is the light spoken of in Psalm 36 [35]:9: In thy light we shall see light.