Whether grace is the principle of merit through charity rather than the other virtues?
Objection 1: It would seem that grace is not the principle of merit through charity rather than the other virtues. For wages are due to work, according to Mat. 20:8: "Call the laborers and pay them their hire." Now every virtue is a principle of some operation, since virtue is an operative habit, as stated above (Q 55, A 2). Hence every virtue is equally a principle of merit.
Objection 2: Further, the Apostle says (1 Cor. 3:8): "Every man shall receive his own reward according to his labor." Now charity lessens rather than increases the labor, because as Augustine says (De Verbis Dom., Serm. lxx), "love makes all hard and repulsive tasks easy and next to nothing." Hence charity is no greater principle of merit than any other virtue.
Objection 3: Further, the greatest principle of merit would seem to be the one whose acts are most meritorious. But the acts of faith and patience or fortitude would seem to be the most meritorious, as appears in the martyrs, who strove for the faith patiently and bravely even till death. Hence other virtues are a greater principle of merit than charity.
On the contrary, Our Lord said (Jn. 14:21): "He that loveth Me, shall be loved of My Father; and I will love him and will manifest Myself to him." Now everlasting life consists in the manifest knowledge of God, according to Jn. 17:3: "This is eternal life: that they may know Thee, the only true" and living "God." Hence the merit of eternal life rests chiefly with charity.
I answer that, As we may gather from what has been stated above (A 1), human acts have the nature of merit from two causes: first and chiefly from the Divine ordination, inasmuch as acts are said to merit that good to which man is divinely ordained. Secondly, on the part of free-will, inasmuch as man, more than other creatures, has the power of voluntary acts by acting by himself. And in both these ways does merit chiefly rest with charity. For we must bear in mind that everlasting life consists in the enjoyment of God. Now the human mind's movement to the fruition of the Divine good is the proper act of charity, whereby all the acts of the other virtues are ordained to this end, since all the other virtues are commanded by charity. Hence the merit of life everlasting pertains first to charity, and secondly, to the other virtues, inasmuch as their acts are commanded by charity. So, likewise, is it manifest that what we do out of love we do most willingly. Hence, even inasmuch as merit depends on voluntariness, merit is chiefly attributed to charity.
Reply to Objection 1: Charity, inasmuch as it has the last end for object, moves the other virtues to act. For the habit to which the end pertains always commands the habits to which the means pertain, as was said above (Q 9, A 1).
Reply to Objection 2: A work can be toilsome and difficult in two ways: first, from the greatness of the work, and thus the greatness of the work pertains to the increase of merit; and thus charity does not lessen the toil---rather, it makes us undertake the greatest toils, "for it does great things, if it exists," as Gregory says (Hom. in Evang. xxx). Secondly, from the defect of the operator; for what is not done with a ready will is hard and difficult to all of us, and this toil lessens merit and is removed by charity.
Reply to Objection 3: The act of faith is not meritorious unless "faith . . . worketh by charity" (Gal. 5:6). So, too, the acts of patience and fortitude are not meritorious unless a man does them out of charity, according to 1 Cor. 13:3: "If I should deliver my body to be burned, and have not charity, it profiteth me nothing."
I–II · Q. 114, Art. 5: Whether a man may merit for himself the first grace?
Whether a man may merit for himself the first grace?
Objection 1: It would seem that a man may merit for himself the first grace, because, as Augustine says (Ep. clxxxvi), "faith merits justification." Now a man is justified by the first grace. Therefore a man may merit the first grace.
Objection 2: Further, God gives grace only to the worthy. Now, no one is said to be worthy of some good, unless he has merited it condignly. Therefore we may merit the first grace condignly.
Objection 3: Further, with men we may merit a gift already received. Thus if a man receives a horse from his master, he merits it by a good use of it in his master's service. Now God is much more bountiful than man. Much more, therefore, may a man, by subsequent works, merit the first grace already received from God.
On the contrary, The nature of grace is repugnant to reward of works, according to Rom. 4:4: "Now to him that worketh, the reward is not reckoned according to grace but according to debt." Now a man merits what is reckoned to him according to debt, as the reward of his works. Hence a man may not merit the first grace.
I answer that, The gift of grace may be considered in two ways: first in the nature of a gratuitous gift, and thus it is manifest that all merit is repugnant to grace, since as the Apostle says (Rom. 11:6), "if by grace, it is not now by works." Secondly, it may be considered as regards the nature of the thing given, and thus, also, it cannot come under the merit of him who has not grace, both because it exceeds the proportion of nature, and because previous to grace a man in the state of sin has an obstacle to his meriting grace, viz. sin. But when anyone has grace, the grace already possessed cannot come under merit, since reward is the term of the work, but grace is the principle of all our good works, as stated above (Q 109). But of anyone merits a further gratuitous gift by virtue of the preceding grace, it would not be the first grace. Hence it is manifest that no one can merit for himself the first grace.
Reply to Objection 1: As Augustine says (Retract. i, 23), he was deceived on this point for a time, believing the beginning of faith to be from us, and its consummation to be granted us by God; and this he here retracts. And seemingly it is in this sense that he speaks of faith as meriting justification. But if we suppose, as indeed it is a truth of faith, that the beginning of faith is in us from God, the first act must flow from grace; and thus it cannot be meritorious of the first grace. Therefore man is justified by faith, not as though man, by believing, were to merit justification, but that, he believes, whilst he is being justified; inasmuch as a movement of faith is required for the justification of the ungodly, as stated above (Q 113, A 4).
Reply to Objection 2: God gives grace to none but to the worthy, not that they were previously worthy, but that by His grace He makes them worthy, Who alone "can make him clean that is conceived of unclean seed" (Job 14:4).
Reply to Objection 3: Man's every good work proceeds from the first grace as from its principle; but not from any gift of man. Consequently, there is no comparison between gifts of grace and gifts of men.