Commentaria in Summam contra Gentiles, Liber III

Because it was shown above ¹ that the immobility of divine providence does not impose necessity on things foreseen, St. Thomas intends to show that neither does it exclude the utility of prayer ².

Concerning this, however, he does two things: first, he shows the proposition; second, in the following chapter, he shows that it is not unfitting if the petitions of those who pray are not always granted by God ³.

I. Regarding the first, having premised that prayer is poured forth to God not so that the eternal disposition of providence may be changed, but so that one may attain what one desires, it is argued first as follows. It belongs to the supereminence of the divine goodness to distribute being and well-being to all things according to a certain order. But all things naturally desire the good. Therefore it is fitting that, in accordance with His goodness, He fulfill the pious desires that are expressed through prayer.

Note that the sense of this reason is: — Because it belongs to the divine goodness to distribute being and well-being to all things according to a certain order—that is, to give one goodness to a thing through the mediation of another, and to use intermediate causes to bestow goodness on things according to the condition of their nature; and the natural order of each thing to the good is through the mediation of desire, because naturally every thing tends to its own good through an inclination, which is here called desire: it is fitting that God grant to the creature its good through the mediation of the desire for the good, just as He also produces some effects through the mediation of other causes. But this is to fulfill the creature's desire. Therefore, it is fitting that He fulfill the creature's desire. — Now, the rational creature expresses its desire through prayer. Therefore, it is fitting that God fulfill the desires of the rational creature expressed through prayer.

II. Concerning the conclusion itself, however, it should be noted from the teaching of St. Thomas in IIª IIae, q. 83, a. 1, and IV Sent., d. 15, ⁴ that prayer, as we speak of prayer here and concerning which theologians determine many things, signifies nothing other than a certain petition that man makes to God. Whence Augustine, in the book De Verbis Domini, ⁵ says that prayer is a certain petition; and Damascene, in the third book, ⁶ says that prayer is a petition of fitting things from God. Moreover, just as commanding is properly an act of reason, because through command subjects are applied by the commander to the attainment of what is desired, in which is implied a certain ordering of one disposing that something is to be done through another; so prayer belongs to the reason; for it is an act of reason ordering in some way that something be done by another who is not an inferior, while asking that it be done by him.

Yet, although prayer is formally an act of reason, it nevertheless presupposes desire as the principle from which it is caused: for it is a petition from God for the execution of a desire. Therefore vocal prayer, which immediately signifies the act of the reason pleading, mediately signifies the desire itself of the will, as the principle and origin from which it proceeds.

From these things it follows that it is the same to say that God fulfills desires expressed through prayer, and that God fulfills the prayers of those who pray. But although they are the same, the nature of prayer is more fully explained by the former. For this reason St. Thomas, in order to explain the nature of prayer more fully, since he proposed that the utility of prayer is not excluded by the immobility of providence, and consequently it had to be proved that God sometimes confers certain goods through the mediation of prayers, concludes that it is fitting for God to fulfill pious desires that are expressed through prayer.

It should also be noted that St. Thomas does not say absolutely that it is fitting for God to fulfill desires, but that He fulfill pious desires. For not all desires expressed through prayer deserve to be heard, as if someone were to ask for the accomplishment of some sin, but those that concern things necessary and useful for salvation, which are called pious desires.

III. Secondly. Every desire is a certain motion toward the good. This cannot be in things except from God. Therefore, etc. The antecedent is proved regarding its second part: because God is good by essence, and the source of goodness. And regarding the first part: because every mover moves toward something like itself. — The consequence, moreover, is proved. Because it belongs to the mover to lead that which is moved to its end. A sign of this is that by the same nature something is moved toward the end, and attains the end, and rests in it.

Concerning that proposition, The motion of desire toward the good cannot be in things except from God, it should be noted that by this St. Thomas does not intend to exclude the proximate causes of desire: but he wishes only to maintain this, that this motion is from God as from the first and principal cause, inasmuch as such a motion toward the good does not proceed from free choice except as it is moved by God. For if it is a desire of nature, it is clear that it is from God, since He is the author of all nature. But if it is a desire of the will, it is clear from the preceding ⁷ that He alone moves the will and applies it to operation by operating interiorly.

IV. Thirdly. The impression of the divine motion is more efficacious in intellectual substances than in other natural substances. But natural things, through the divine motion, attain a natural appetite for the good and the completion of the appetite by attaining their proper ends. Therefore much more so do intellectual substances. — The major is proved. Because the closer things are to the mover, the more efficaciously do they receive the impression of the mover, as is evident in those things that are heated by fire. But intellectual substances are closer to God than inanimate natural substances.

Fourthly. God loves His creature, and more so that which participates more in His goodness, as was shown above. Therefore He wills the desires of the rational creature to be fulfilled, which participate most perfectly in the divine goodness. Therefore, etc. — The first consequence is proved. Because it belongs to the nature of friendship that the lover wills the desire of the beloved to be fulfilled, inasmuch as he wills his good: whence it is said that friends have the same will. — The second, moreover, is proved. Because the will of God is the most perfect cause, since He through His will is the cause of things.

Fifthly. It is most praiseworthy among men not to deny assent to those who ask justly, since on this account they are called liberal, clement, merciful, and pious. Therefore, etc. — The consequence is proved. Because the good of the creature is derived by a certain likeness from the divine goodness.

It is confirmed by the authority of the Psalm, and Matt. 7.