Whither can I go from thy spiritwhither can I flee from thy presence?If I ascend into heaven, thou are there;if I am prostrate in the abyss, thou art there.(Ps. 138:7-8)
Although I often and earnestly directed my thought to this end, and at some times that which I sought seemed to be just within my reach, while again it wholly evaded my mental vision, at last in despair I was about to cease, as if from the search for a thing which could not be found. But when I wished to exclude this thought altogether, lest, by busying my mind to no purpose, it should keep me from other thoughts, in which I might be successful; then more and more, though I was unwilling and shunned it, it began to force itself upon me, with a kind of importunity. So, one day, when I was exceedingly wearied with resisting its importunity, in the very conflict of my thoughts, the proof of which I had despaired offered itself, so that I eagerly embraced the thoughts which I was strenuously repelling.
Similarly, in Cur Deus Homo:
The first contains the objections of infidels, who despise the Christian faith because they deem it contrary to reason; and also the reply of believers; and, in fine, leaving Christ out of view (as if nothing had ever been known of him), it proves, by absolute reasons, the impossibility that any man should be saved without him. Again, in the second book, likewise, as if nothing were known of Christ, it is moreover shown by plain reasoning and fact that human nature was ordained for this purpose, viz., that every man should enjoy a happy immortality, both in body and in soul; and that it was necessary that this design for which man was made should be fulfilled; but that it could not be fulfilled unless God became man, and unless all things were to take place which we hold with regard to Christ.
The necessity of the Incarnation becomes clear when our knowledge of it is denied, just as God’s attributes emerge from the unum argumentum precisely when we both deny Biblical revelation, proceeding sola ratione, and even the search for reason altogether. God is still there, in the abyss.