Summa Th. I-II EN Qu.69 a.4

Whether the rewards of the beatitudes are suitably enumerated?

Objection: 1. It would seem that the rewards of the beatitudes are unsuitably enumerated. Because the kingdom of heaven, which is eternal life, contains all good things. Therefore, once given the kingdom of heaven, no other rewards should be mentioned.
2. Further, the kingdom of heaven is assigned as the reward, both of the first and of the eighth beatitude. Therefore, on the same ground it should have been assigned to all.
3. Further, the beatitudes are arranged in the ascending order, as Augustine remarks (De Serm. Dom. in Monte i, 4): whereas the rewards seem to be placed in the descending order, since to "possess the land" is less than to possess "the kingdom of heaven." Therefore these rewards are unsuitably enumerated.

On the contrary stands the authority of Our Lord Who propounded these rewards.
I answer that These rewards are most suitably assigned, considering the nature of the beatitudes in relation to the three kinds of happiness indicated above (Article [3]). For the first three beatitudes concerned the withdrawal of man from those things in which sensual happiness consists: which happiness man desires by seeking the object of his natural desire, not where he should seek it, viz. in God, but in temporal and perishable things. Wherefore the rewards of the first three beatitudes correspond to these things which some men seek to find in earthly happiness. For men seek in external things, viz. riches and honors, a certain excellence and abundance, both of which are implied in the kingdom of heaven, whereby man attains to excellence and abundance of good things in God. Hence Our Lord promised the kingdom of heaven to the poor in spirit. Again, cruel and pitiless men seek by wrangling and fighting to destroy their enemies so as to gain security for themselves. Hence Our Lord promised the meek a secure and peaceful possession of the land of the living, whereby the solid reality of eternal goods is denoted. Again, men seek consolation for the toils of the present life, in the lusts and pleasures of the world. Hence Our Lord promises comfort to those that mourn.Two other beatitudes belong to the works of active happiness, which are the works of virtues directing man in his relations to his neighbor: from which operations some men withdraw through inordinate love of their own good. Hence Our Lord assigns to these beatitudes rewards in correspondence with the motives for which men recede from them. For there are some who recede from acts of justice, and instead of rendering what is due, lay hands on what is not theirs, that they may abound in temporal goods. Wherefore Our Lord promised those who hunger after justice, that they shall have their fill. Some, again, recede from works of mercy, lest they be busied with other people's misery. Hence Our Lord promised the merciful that they should obtain mercy, and be delivered from all misery.The last two beatitudes belong to contemplative happiness or beatitude: hence the rewards are assigned in correspondence with the dispositions included in the merit. For cleanness of the eye disposes one to see clearly: hence the clean of heart are promised that they shall see God. Again, to make peace either in oneself or among others, shows a man to be a follower of God, Who is the God of unity and peace. Hence, as a reward, he is promised the glory of the Divine sonship, consisting in perfect union with God through consummate wisdom.

Reply to Objection: 1. As Chrysostom says (Hom. xv in Matth.), all these rewards are one in reality, viz. eternal happiness, which the human intellect cannot grasp. Hence it was necessary to describe it by means of various boons known to us, while observing due proportion to the merits to which those rewards are assigned.
2. Just as the eighth beatitude is a confirmation of all the beatitudes, so it deserves all the rewards of the beatitudes. Hence it returns to the first, that we may understand all the other rewards to be attributed to it in consequence. Or else, according to Ambrose (Super Luc. v), the kingdom of heaven is promised to the poor in spirit, as regards the glory of the soul; but to those who suffer persecution in their bodies, it is promised as regards the glory of the body.
3. The rewards are also arranged in ascending order. For it is more to possess the land of the heavenly kingdom than simply to have it: since we have many things without possessing them firmly and peacefully. Again, it is more to be comforted in the kingdom than to have and possess it, for there are many things the possession of which is accompanied by sorrow. Again, it is more to have one's fill than simply to be comforted, because fulness implies abundance of comfort. And mercy surpasses satiety, for thereby man receives more than he merited or was able to desire. And yet more is it to see God, even as he is a greater man who not only dines at court, but also sees the king's countenance. Lastly, the highest place in the royal palace belongs to the king's son.


We must now consider the Fruits of the Holy Ghost: under which head there are four points of inquiry:

(1) Whether the fruits of the Holy Ghost are acts?

(2) Whether they differ from the beatitudes?

(3) Of their number?

(4) Of their opposition to the works of the flesh.

Whether the fruits of the Holy Ghost which the Apostle enumerates (@Ga 5@) are acts?

Objection: 1. It would seem that the fruits of the Holy Ghost, enumerated by the Apostle (Ga 5,22-23), are not acts. For that which bears fruit, should not itself be called a fruit, else we should go on indefinitely. But our actions bear fruit: for it is written (Sg 3,15): "The fruit of good labor is glorious," and (Jn 4,36): "He that reapeth receiveth wages, and gathereth fruit unto life everlasting." Therefore our actions are not to be called fruits.
2. Further, as Augustine says (De Trin. x, 10), "we enjoy [*'Fruimur', from which verb we have the Latin 'fructus' and the English 'fruit'] the things we know, when the will rests by rejoicing in them." But our will should not rest in our actions for their own sake. Therefore our actions should not be called fruits.
3. Further, among the fruits of the Holy Ghost, the Apostle numbers certain virtues, viz. charity, meekness, faith, and chastity. Now virtues are not actions but habits, as stated above (Question [55], Article [1]). Therefore the fruits are not actions.

On the contrary It is written (Mt 12,33): "By the fruit the tree is known"; that is to say, man is known by his works, as holy men explain the passage. Therefore human actions are called fruits.
I answer that The word "fruit" has been transferred from the material to the spiritual world. Now fruit, among material things, is the product of a plant when it comes to perfection, and has a certain sweetness. This fruit has a twofold relation: to the tree that produces it, and to the man who gathers the fruit from the tree. Accordingly, in spiritual matters, we may take the word "fruit" in two ways: first, so that the fruit of man, who is likened to the tree, is that which he produces; secondly, so that man's fruit is what he gathers.Yet not all that man gathers is fruit, but only that which is last and gives pleasure. For a man has both a field and a tree, and yet these are not called fruits; but that only which is last, to wit, that which man intends to derive from the field and from the tree. In this sense man's fruit is his last end which is intended for his enjoyment.If, however, by man's fruit we understand a product of man, then human actions are called fruits: because operation is the second act of the operator, and gives pleasure if it is suitable to him. If then man's operation proceeds from man in virtue of his reason, it is said to be the fruit of his reason: but if it proceeds from him in respect of a higher power, which is the power of the Holy Ghost, then man's operation is said to be the fruit of the Holy Ghost, as of a Divine seed, for it is written (1Jn 3,9): "Whosoever is born of God, committeth no sin, for His seed abideth in him."

Reply to Objection: 1. Since fruit is something last and final, nothing hinders one fruit bearing another fruit, even as one end is subordinate to another. And so our works, in so far as they are produced by the Holy Ghost working in us, are fruits: but, in so far as they are referred to the end which is eternal life, they should rather be called flowers: hence it is written (Si 24,23): "My flowers are the fruits of honor and riches."
2. When the will is said to delight in a thing for its own sake, this may be understood in two ways. First, so that the expression "for the sake of" be taken to designate the final cause; and in this way, man delights in nothing for its own sake, except the last end. Secondly, so that it expresses the formal cause; and in this way, a man may delight in anything that is delightful by reason of its form. Thus it is clear that a sick man delights in health, for its own sake, as in an end; in a nice medicine, not as in an end, but as in something tasty; and in a nasty medicine, nowise for its own sake, but only for the sake of something else. Accordingly we must say that man must delight in God for His own sake, as being his last end, and in virtuous deeds, not as being his end, but for the sake of their inherent goodness which is delightful to the virtuous. Hence Ambrose says (De Parad. xiii) that virtuous deeds are called fruits because "they refresh those that have them, with a holy and genuine delight."
3. Sometimes the names of the virtues are applied to their actions: thus Augustine writes (Tract. xl in Joan.): "Faith is to believe what thou seest not"; and (De Doctr. Christ. iii, 10): "Charity is the movement of the soul in loving God and our neighbor." It is thus that the names of the virtues are used in reckoning the fruits.

Whether the fruits differ from the beatitudes?

Objection: 1. It would seem that the fruits do not differ from the beatitudes. For the beatitudes are assigned to the gifts, as stated above (Question [69], Article [1], ad 1). But the gifts perfect man in so far as he is moved by the Holy Ghost. Therefore the beatitudes themselves are fruits of the Holy Ghost.
2. Further, as the fruit of eternal life is to future beatitude which is that of actual possession, so are the fruits of the present life to the beatitudes of the present life, which are based on hope. Now the fruit of eternal life is identified with future beatitude. Therefore the fruits of the present life are the beatitudes.
3. Further, fruit is essentially something ultimate and delightful. Now this is the very nature of beatitude, as stated above (Question [3], Article [1]; Question [4], Article [1]). Therefore fruit and beatitude have the same nature, and consequently should not be distinguished from one another.

On the contrary Things divided into different species, differ from one another. But fruits and beatitudes are divided into different parts, as is clear from the way in which they are enumerated. Therefore the fruits differ from the beatitudes.
I answer that More is required for a beatitude than for a fruit. Because it is sufficient for a fruit to be something ultimate and delightful; whereas for a beatitude, it must be something perfect and excellent. Hence all the beatitudes may be called fruits, but not vice versa. For the fruits are any virtuous deeds in which one delights: whereas the beatitudes are none but perfect works, and which, by reason of their perfection, are assigned to the gifts rather than to the virtues, as already stated (Question [69], Article [1], ad 1).

Reply to Objection: 1. This argument proves the beatitudes to be fruits, but not that all the fruits are beatitudes.
2. The fruit of eternal life is ultimate and perfect simply: hence it nowise differs from future beatitude. On the other hand the fruits of the present life are not simply ultimate and perfect; wherefore not all the fruits are beatitudes.
3. More is required for a beatitude than for a fruit, as stated.

Whether the fruits are suitably enumerated by the Apostle?

Objection: 1. It would seem that the fruits are unsuitably enumerated by the Apostle (Ga 5,22-23). Because, elsewhere, he says that there is only one fruit of the present life; according to Rm 6,22: "You have your fruit unto sanctification." Moreover it is written (Is 27,9): "This is all the fruit . . . that the sin . . . be taken away." Therefore we should not reckon twelve fruits.
2. Further, fruit is the product of spiritual seed, as stated (Article [1]). But Our Lord mentions (Mt 13,23) a threefold fruit as growing from a spiritual seed in a good ground, viz. "hundredfold, sixtyfold," and "thirtyfold." Therefore one should not reckon twelve fruits.
3. Further, the very nature of fruit is to be something ultimate and delightful. But this does not apply to all the fruits mentioned by the Apostle: for patience and long-suffering seem to imply a painful object, while faith is not something ultimate, but rather something primary and fundamental. Therefore too many fruits are enumerated.
4. On the other hand, It seems that they are enumerated insufficiently and incompletely. For it has been stated (Article [2]) that all the beatitudes may be called fruits; yet not all are mentioned here. Nor is there anything corresponding to the acts of wisdom, and of many other virtues. Therefore it seems that the fruits are insufficiently enumerated.

On the contrary
I answer that The number of the twelve fruits enumerated by the Apostle is suitable, and that there may be a reference to them in the twelve fruits of which it is written (Ap 22,2): "On both sides of the river was the tree bearing twelve fruits." Since, however, a fruit is something that proceeds from a source as from a seed or root, the difference between these fruits must be gathered from the various ways in which the Holy Ghost proceeds in us: which process consists in this, that the mind of man is set in order, first of all, in regard to itself; secondly, in regard to things that are near it; thirdly, in regard to things that are below it.Accordingly man's mind is well disposed in regard to itself when it has a good disposition towards good things and towards evil things. Now the first disposition of the human mind towards the good is effected by love, which is the first of our emotions and the root of them all, as stated above (Question [27], Article [4]). Wherefore among the fruits of the Holy Ghost, we reckon "charity," wherein the Holy Ghost is given in a special manner, as in His own likeness, since He Himself is love. Hence it is written (Rm 5,5): "The charity of God is poured forth in our hearts by the Holy Ghost, Who is given to us." The necessary result of the love of charity is joy: because every lover rejoices at being united to the beloved. Now charity has always actual presence in God Whom it loves, according to 1Jn 4,16: "He that abideth in charity, abideth in God, and God in Him": wherefore the sequel of charity is "joy." Now the perfection of joy is peace in two respects. First, as regards freedom from outward disturbance; for it is impossible to rejoice perfectly in the beloved good, if one is disturbed in the enjoyment thereof; and again, if a man's heart is perfectly set at peace in one object, he cannot be disquieted by any other, since he accounts all others as nothing; hence it is written (Ps 118,165): "Much peace have they that love Thy Law, and to them there is no stumbling-block," because, to wit, external things do not disturb them in their enjoyment of God. Secondly, as regards the calm of the restless desire: for he does not perfectly rejoice, who is not satisfied with the object of his joy. Now peace implies these two things, namely, that we be not disturbed by external things, and that our desires rest altogether in one object. Wherefore after charity and joy, "peace" is given the third place. In evil things the mind has a good disposition, in respect of two things. First, by not being disturbed whenever evil threatens: which pertains to "patience"; secondly, by not being disturbed, whenever good things are delayed; which belongs to "long suffering," since "to lack good is a kind of evil" (Ethic. v, 3).Man's mind is well disposed as regards what is near him, viz. his neighbor, first, as to the will to do good; and to this belongs "goodness." Secondly, as to the execution of well-doing; and to this belongs "benignity," for the benign are those in whom the salutary flame [bonus ignis] of love has enkindled the desire to be kind to their neighbor. Thirdly, as to his suffering with equanimity the evils his neighbor inflicts on him. To this belongs "meekness," which curbs anger. Fourthly, in the point of our refraining from doing harm to our neighbor not only through anger, but also through fraud or deceit. To this pertains "faith," if we take it as denoting fidelity. But if we take it for the faith whereby we believe in God, then man is directed thereby to that which is above him, so that he subject his intellect and, consequently, all that is his, to God.Man is well disposed in respect of that which is below him, as regards external action, by "modesty," whereby we observe the "mode" in all our words and deeds: as regards internal desires, by "contingency" and "chastity": whether these two differ because chastity withdraws man from unlawful desires, contingency also from lawful desires: or because the continent man is subject to concupiscence, but is not led away; whereas the chaste man is neither subject to, nor led away from them.

Reply to Objection: 1. Sanctification is effected by all the virtues, by which also sins are taken away. Consequently fruit is mentioned there in the singular, on account of its being generically one, though divided into many species which are spoken of as so many fruits.
2. The hundredfold, sixtyfold, and thirtyfold fruits do not differ as various species of virtuous acts, but as various degrees of perfection, even in the same virtue. Thus contingency of the married state is said to be signified by the thirtyfold fruit; the contingency of widowhood, by the sixtyfold; and virginal contingency, by the hundredfold fruit. There are, moreover, other ways in which holy men distinguish three evangelical fruits according to the three degrees of virtue: and they speak of three degrees, because the perfection of anything is considered with respect to its beginning, its middle, and its end.
3. The fact of not being disturbed by painful things is something to delight in. And as to faith, if we consider it as the foundation, it has the aspect of being ultimate and delightful, in as much as it contains certainty: hence a gloss expounds thus: "Faith, which is certainly about the unseen."
4. As Augustine says on Ga 5,22-23, "the Apostle had no intention of teaching us how many [either works of the flesh, or fruits of the Spirit] there are; but to show how the former should be avoided, and the latter sought after." Hence either more or fewer fruits might have been mentioned. Nevertheless, all the acts of the gifts and virtues can be reduced to these by a certain kind of fittingness, in so far as all the virtues and gifts must needs direct the mind in one of the above-mentioned ways. Wherefore the acts of wisdom and of any gifts directing to good, are reduced to charity, joy and peace. The reason why he mentions these rather than others, is that these imply either enjoyment of good things, or relief from evils, which things seem to belong to the notion of fruit.

Whether the fruits of the Holy Ghost are contrary to the works of the flesh?

Objection: 1. It would seem that the fruits of the Holy Ghost are not contrary to the works of the flesh, which the Apostle enumerates (Ga 5,19, seqq.). Because contraries are in the same genus. But the works of the flesh are not called fruits. Therefore the fruits of the Spirit are not contrary to them.
2. Further, one thing has a contrary. Now the Apostle mentions more works of the flesh than fruits of the Spirit. Therefore the fruits of the Spirit and the works of the flesh are not contrary to one another.
3. Further, among the fruits of the Spirit, the first place is given to charity, joy, and peace: to which, fornication, uncleanness, and immodesty, which are the first of the works of the flesh are not opposed. Therefore the fruits of the Spirit are not contrary to the works of the flesh.

On the contrary The Apostle says (Ga 5,17) that "the flesh lusteth against the spirit, and the spirit against the flesh."
I answer that The works of the flesh and the fruits of the Spirit may be taken in two ways. First, in general: and in this way the fruits of the Holy Ghost considered in general are contrary to the works of the flesh. Because the Holy Ghost moves the human mind to that which is in accord with reason, or rather to that which surpasses reason: whereas the fleshly, viz. the sensitive, appetite draws man to sensible goods which are beneath him. Wherefore, since upward and downward are contrary movements in the physical order, so in human actions the works of the flesh are contrary to the fruits of the Spirit.Secondly, both fruits and fleshly works as enumerated may be considered singly, each according to its specific nature. And in this they are not of necessity contrary each to each: because, as stated above (Article [3], ad 4), the Apostle did not intend to enumerate all the works, whether spiritual or carnal. However, by a kind of adaptation, Augustine, commenting on Ga 5,22-23, contrasts the fruits with the carnal works, each to each. Thus "to fornication, which is the love of satisfying lust outside lawful wedlock, we may contrast charity, whereby the soul is wedded to God: wherein also is true chastity. By uncleanness we must understand whatever disturbances arise from fornication: and to these the joy of tranquillity is opposed. Idolatry, by reason of which war was waged against the Gospel of God, is opposed to peace. Against witchcrafts, enmities, contentions, emulations, wraths and quarrels, there is longsuffering, which helps us to bear the evils inflicted on us by those among whom we dwell; while kindness helps us to cure those evils; and goodness, to forgive them. In contrast to heresy there is faith; to envy, mildness; to drunkenness and revellings, contingency."

Reply to Objection: 1. That which proceeds from a tree against the tree's nature, is not called its fruit, but rather its corruption. And since works of virtue are connatural to reason, while works of vice are contrary to nature, therefore it is that works of virtue are called fruits, but not so works of vice.
2. "Good happens in one way, evil in all manner of ways," as Dionysius says (Div. Nom. iv): so that to one virtue many vices are contrary. Consequently we must not be surprised if the works of the flesh are more numerous than the fruits of the spirit.
3. The Reply to the Third Objection is clear from what has been said.

EVIL HABITS, i.e. VICES AND SINS (Questions [71]-89)


We have in the next place to consider vice and sin: about which six points have to be considered: (1) Vice and sin considered in themselves; (2) their distinction; (3) their comparison with one another; (4) the subject of sin; (5) the cause of sin; (6) the effect of sin.

Under the first head there are six points of inquiry:

(1) Whether vice is contrary to virtue?

(2) Whether vice is contrary to nature?

(3) Which is worse, a vice or a vicious act?

(4) Whether a vicious act is compatible with virtue?

(5) Whether every sin includes action?

(6) Of the definition of sin proposed by Augustine (Contra Faust. xxii): "Sin is a word, deed, or desire against the eternal law."

Whether vice is contrary to virtue?

Objection: 1. It would seem that vice is not contrary to virtue. For one thing has one contrary, as proved in Metaph. x, text. 17. Now sin and malice are contrary to virtue. Therefore vice is not contrary to it: since vice applies also to undue disposition of bodily members or of any things whatever.
2. Further, virtue denotes a certain perfection of power. But vice does not denote anything relative to power. Therefore vice is not contrary to virtue.
3. Further, Cicero (De Quaest. Tusc. iv) says that "virtue is the soul's health." Now sickness or disease, rather than vice, is opposed to health. Therefore vice is not contrary to virtue.

On the contrary Augustine says (De Perfect. Justit. ii) that "vice is a quality in respect of which the soul is evil." But "virtue is a quality which makes its subject good," as was shown above (Question [55], Articles [3],4). Therefore vice is contrary to virtue.
I answer that Two things may be considered in virtue---the essence of virtue, and that to which virtue is ordained. In the essence of virtue we may consider something directly, and we may consider something consequently. Virtue implies "directly" a disposition whereby the subject is well disposed according to the mode of its nature: wherefore the Philosopher says (Phys. vii, text. 17) that "virtue is a disposition of a perfect thing to that which is best; and by perfect I mean that which is disposed according to its nature." That which virtue implies "consequently" is that it is a kind of goodness: because the goodness of a thing consists in its being well disposed according to the mode of its nature. That to which virtue is directed is a good act, as was shown above (Question [56], Article [3]).Accordingly three things are found to be contrary to virtue. One of these is "sin," which is opposed to virtue in respect of that to which virtue is ordained: since, properly speaking, sin denotes an inordinate act; even as an act of virtue is an ordinate and due act: in respect of that which virtue implies consequently, viz. that it is a kind of goodness, the contrary of virtue is "malice": while in respect of that which belongs to the essence of virtue directly, its contrary is "vice": because the vice of a thing seems to consist in its not being disposed in a way befitting its nature: hence Augustine says (De Lib. Arb. iii): "Whatever is lacking for a thing's natural perfection may be called a vice."

Reply to Objection: 1. These three things are contrary to virtue, but not in the same respect: for sin is opposed to virtue, according as the latter is productive of a good work; malice, according as virtue is a kind of goodness; while vice is opposed to virtue properly as such.
2. Virtue implies not only perfection of power, the principle of action; but also the due disposition of its subject. The reason for this is because a thing operates according as it is in act: so that a thing needs to be well disposed if it has to produce a good work. It is in this respect that vice is contrary to virtue.
3. As Cicero says (De Quaest. Tusc. iv), "disease and sickness are vicious qualities," for in speaking of the body "he calls it" disease "when the whole body is infected," for instance, with fever or the like; he calls it sickness "when the disease is attended with weakness"; and vice "when the parts of the body are not well compacted together." And although at times there may be disease in the body without sickness, for instance, when a man has a hidden complaint without being hindered outwardly from his wonted occupations; "yet, in the soul," as he says, "these two things are indistinguishable, except in thought." For whenever a man is ill-disposed inwardly, through some inordinate affection, he is rendered thereby unfit for fulfilling his duties: since "a tree is known by its fruit," i.e. man by his works, according to Mt 12,33. But "vice of the soul," as Cicero says (De Quaest. Tusc. iv), "is a habit or affection of the soul discordant and inconsistent with itself through life": and this is to be found even without disease and sickness, e.g. when a man sins from weakness or passion. Consequently vice is of wider extent than sickness or disease; even as virtue extends to more things than health; for health itself is reckoned a kind of virtue (Phys. vii, text. 17). Consequently vice is reckoned as contrary to virtue, more fittingly than sickness or disease.

Whether vice is contrary to nature?

Objection: 1. It would seem that vice is not contrary to nature. Because vice is contrary to virtue, as stated above (Article [1]). Now virtue is in us, not by nature but by infusion or habituation, as stated above (Question [63], Articles [1],2,3). Therefore vice is not contrary to nature.
2. Further, it is impossible to become habituated to that which is contrary to nature: thus "a stone never becomes habituated to upward movement" (Ethic. ii, 1). But some men become habituated to vice. Therefore vice is not contrary to nature.
3. Further, anything contrary to a nature, is not found in the greater number of individuals possessed of that nature. Now vice is found in the greater number of men; for it is written (Mt 7,13): "Broad is the way that leadeth to destruction, and many there are who go in thereat." Therefore vice is not contrary to nature.
4. Further, sin is compared to vice, as act to habit, as stated above (Article [1]). Now sin is defined as "a word, deed, or desire, contrary to the Law of God," as Augustine shows (Contra Faust. xxii, 27). But the Law of God is above nature. Therefore we should say that vice is contrary to the Law, rather than to nature.

On the contrary Augustine says (De Lib. Arb. iii, 13): "Every vice, simply because it is a vice, is contrary to nature."
I answer that As stated above (Article [1]), vice is contrary to virtue. Now the virtue of a thing consists in its being well disposed in a manner befitting its nature, as stated above (Article [1]). Hence the vice of any thing consists in its being disposed in a manner not befitting its nature, and for this reason is that thing "vituperated," which word is derived from "vice" according to Augustine (De Lib. Arb. iii, 14).But it must be observed that the nature of a thing is chiefly the form from which that thing derives its species. Now man derives his species from his rational soul: and consequently whatever is contrary to the order of reason is, properly speaking, contrary to the nature of man, as man; while whatever is in accord with reason, is in accord with the nature of man, as man. Now "man's good is to be in accord with reason, and his evil is to be against reason," as Dionysius states (Div. Nom. iv). Therefore human virtue, which makes a man good, and his work good, is in accord with man's nature, for as much as it accords with his reason: while vice is contrary to man's nature, in so far as it is contrary to the order of reason.

Reply to Objection: 1. Although the virtues are not caused by nature as regards their perfection of being, yet they incline us to that which accords with reason, i.e. with the order of reason. For Cicero says (De Inv. Rhet. ii) that "virtue is a habit in accord with reason, like a second nature": and it is in this sense that virtue is said to be in accord with nature, and on the other hand that vice is contrary to nature.
2. The Philosopher is speaking there of a thing being against nature, in so far as "being against nature" is contrary to "being from nature": and not in so far as "being against nature" is contrary to "being in accord with nature," in which latter sense virtues are said to be in accord with nature, in as much as they incline us to that which is suitable to nature.
3. There is a twofold nature in man, rational nature, and the sensitive nature. And since it is through the operation of his senses that man accomplishes acts of reason, hence there are more who follow the inclinations of the sensitive nature, than who follow the order of reason: because more reach the beginning of a business than achieve its completion. Now the presence of vices and sins in man is owing to the fact that he follows the inclination of his sensitive nature against the order of his reason.
4. Whatever is irregular in a work of art, is unnatural to the art which produced that work. Now the eternal law is compared to the order of human reason, as art to a work of art. Therefore it amounts to the same that vice and sin are against the order of human reason, and that they are contrary to the eternal law. Hence Augustine says (De Lib. Arb. iii, 6) that "every nature, as such, is from God; and is a vicious nature, in so far as it fails from the Divine art whereby it was made."

Summa Th. I-II EN Qu.69 a.4