Gregory of Nazianzus

The truth, and the whole Word, is full of difficulty and obscurity; and as it were with a small instrument we are undertaking a great work, when with merely human wisdom we pursue the knowledge of the self-existent, and in company with, or not apart from, the senses, by which we are borne hither and thither and led into error, we apply ourselves to the search after things that are only to be grasped by the mind, and we are unable by meeting bare realities with bare intellect to approximate somewhat more closely to the truth and to mold the mind by its concepts. Now the subject of God is harder to come at, in proportion as it is more perfect than any other and is open to more objections, and the solutions of them are more laborious. For every objection, however small, stops and hinders the course of our argument and cuts off its further advance, just like people who suddenly check with the rein the horses in full career and turn them right round by the unexpected shock. Thus Solomon, who was the wisest of all people, whether before him or in his own time, to whom God gave breadth of heart and a flood of contemplation, more abundant than the sand, even he, the more he entered into the depth, the more dizzy he became, and he declared the furthest point of wisdom to be the discovery of how very far off it was from him.