Summa contra Gentiles1.5 Chapter V. That those things which cannot be investigated by reason are fittingly proposed to man as an object of faith

It may appear to some that those things which cannot be investigated by reason ought not to be proposed to man as an object of faith: because divine wisdom provides for each thing according to the mode of its nature. We must therefore prove that it is necessary also for those things which surpass reason to be proposed by God to man as an object of faith.

For no man tends to do a thing by his desire and endeavour unless it be pre viously known to him. Wherefore since man is directed by divine providence to a higher good than human frailty can attain in the present life, as we shall show in the sequel,’ it was necessary for his mind to be bidden to something higher than those things to which our reason can reach in the present life, so that he might learn to aspire, and by his endeavours to tend to something surpassing the whole state of the present life. And this is especially competent to the Christian religion, which alone promises goods spiritual and eternal: for which reason it proposes many things surpassing the thought of man: whereas the old law which contained promises of temporal things, proposed few things that are above human inquiry. It was with this motive that the philosophers, in order to wean men from sensible pleasures to virtue, took care to show that there are other goods of greater account than those which appeal to the senses, the taste of which things affords much greater delight to those who devote themselves to active or contemplative virtues.

Again it is necessary for this truth to be proposed to man as an object of faith in order that he may have truer knowledge of God. For then alone do we know God truly, when we believe that He is far above all that man can possibly think of God, because the divine essence surpasses man’s natural knowledge, as stated above.” Hence by the fact that certain things about God are proposed to man, which surpass his reason, he is strengthened in his opinion that God is far above what he is able to think.

There results also another advantage from this, namely, the checking of presumption which is the mother of error. For some there are who presume so far on their wits that they think themselves capable of measuring the whole nature of things by their intellect, in that they esteem all things true which they see, and false which they see not. Accordingly, in order that man’s mind might be freed from this presumption, and seek the truth humbly, it was necessary that certain things far surpassing his intellect should be proposed to man by God.

Yet another advantage is made apparent by the wares of x CHAPTER VI 1 the Philosopher (10 Ethic.). For when a certain Simonides man ought to relish human things, and a mortal, mortal things: the Philosopher contradicted him, saying that a man ought to devote himself to immortal and divine things as much as he can. Hence he says (11 De Animal.)” that though it is but little that we perceive of higher substances, yet that little is more loved and desired than all the knowledge we have of lower substances. He says also (2 De Calo et Mundo)’ that when questions about the heavenly bodies can be answered by a short and probable solution, it happens that the hearer is very much rejoiced. All this shows that however imperfect the knowledge of the highest things may be, it bestows very great perfection on the soul: and consequently, although human reason is unable to grasp fully things that are above reason, it nevertheless acquires much perfection, if at least it hold things, in any way whatever, by faith.

Wherefore it is written (Ecclus. iii. 25): Many things are shown to thee above the understanding of men, and (1 Cor. ii. 10, 15): The things... that are of God no man knoweth, but the Spirit of God: but to us God hath revealed them by His Spin.