33 Wherefore, although I am not able to teach, yet I cease not to advise, that, (whereas many wish to appear wise, and it is no easy matter to discern whether they be fools,) with all earnestness, and with all prayers, and lastly with groans, or even, if so it may be, with tears, you entreat of God to set you free from the evil of error; if your heart be set on a happy life. And this will take place the more easily, if you obey with a willing mind His commands, which He has willed should be confirmed by so great authority of the Catholic Church.
For whereas the wise man is so joined to God in mind, as that there is nothing set between to separate; for God is Truth; and no one is by any means wise, unless his mind come into contact with the Truth; we cannot deny that between the folly of man, and the most pure Truth of God, the wisdom of man is set, as something in the middle. For the wise man, so far as it is given unto him, imitates God; but for a man who is a fool, there is nothing nearer to him, than a man who is wise, for him to imitate with profit: and since, as has been said, it is not easy to understand this one by reason, it behooved that certain miracles be brought near to the very eyes, which fools use with much greater readiness than the mind, that, men being moved by authority, their life and habits might first be cleansed, and they thus rendered capable of receiving reason.
Whereas, therefore, it needed both that man be imitated, and that our hope be not set in man, what could be done on the part of God more full of kindness and grace, than that the very pure, eternal, unchangeable Wisdom of God, unto Whom it behooves us to cleave, should deign to take upon Him (the nature of) man? That not only He might do what should invite us to follow God, but also might suffer what used to deter us from following God. For, whereas no one can attain unto the most sure and chief good, unless he shall fully and perfectly love it; which will by no means take place, so long as the evils of the body and of fortune are dreaded; He by being born after a miraculous manner and working caused Himself to be loved; and by dying and rising again shut out fear.
And, further, in all other matters, which it were long to go through, He showed Himself such, as that we might perceive unto what the clemency of God could be reached forth, and unto what the weakness of man be lifted up.
Source: On the Profit of Believing (New Advent)