Summa Th. I-II EN Qu.88 a.3
Objection: 1. It would seem that venial sin is not a disposition to mortal sin. For one contrary does not dispose to another. But venial and mortal sin are condivided as contrary to one another, as stated above (Article ). Therefore venial sin is not a disposition to mortal sin.
2. Further, an act disposes to something of like species, wherefore it is stated in Ethic. ii, 1,2, that "from like acts like dispositions and habits are engendered." But mortal and venial sin differ in genus or species, as stated above (Article ). Therefore venial sin does not dispose to mortal sin.
3. Further, if a sin is called venial because it disposes to mortal sin, it follows that whatever disposes to mortal sin is a venial sin. Now every good work disposes to mortal sin; wherefore Augustine says in his Rule (Ep. ccxi) that "pride lies in wait for good works that it may destroy them." Therefore even good works would be venial sins, which is absurd.
On the contrary It is written (Si 19,1): "He that contemneth small things shall fall by little and little." Now he that sins venially seems to contemn small things. Therefore by little and little he is disposed to fall away together into mortal sin.
I answer that A disposition is a kind of cause; wherefore as there is a twofold manner of cause, so is there a twofold manner of disposition. For there is a cause which moves directly to the production of the effect, as a hot thing heats: and there is a cause which moves indirectly, by removing an obstacle, as he who displaces a pillar is said to displace the stone that rests on it. Accordingly an act of sin disposes to something in two ways. First, directly, and thus it disposes to an act of like species. In this way, a sin generically venial does not, primarily and of its nature, dispose to a sin generically mortal, for they differ in species. Nevertheless, in this same way, a venial sin can dispose, by way of consequence, to a sin which is mortal on the part of the agent: because the disposition or habit may be so far strengthened by acts of venial sin, that the lust of sinning increases, and the sinner fixes his end in that venial sin: since the end for one who has a habit, as such, is to work according to that habit; and the consequence will be that, by sinning often venially, he becomes disposed to a mortal sin. Secondly, a human act disposes to something by removing an obstacle thereto. In this way a sin generically venial can dispose to a sin generically mortal. Because he that commits a sin generically venial, turns aside from some particular order; and through accustoming his will not to be subject to the due order in lesser matters, is disposed not to subject his will even to the order of the last end, by choosing something that is a mortal sin in its genus.
Reply to Objection: 1. Venial and mortal sin are not condivided in contrariety to one another, as though they were species of one genus, as stated above (Article , ad 1), but as an accident is condivided with substance. Wherefore an accident can be a disposition to a substantial form, so can a venial sin dispose to mortal.
2. Venial sin is not like mortal sin in species; but it is in genus, inasmuch as they both imply a defect of due order, albeit in different ways, as stated (Articles ,2).
3. A good work is not, of itself, a disposition to mortal sin; but it can be the matter or occasion of mortal sin accidentally; whereas a venial sin, of its very nature, disposes to mortal sin, as stated.
Objection: 1. It would seem that a venial sin can become a mortal sin. For Augustine in explaining the words of Jn 3,36: "He that believeth not the Son, shall not see life," says (Tract. xii in Joan.): "The slightest," i.e. venial, "sins kill if we make little of them." Now a sin is called mortal through causing the spiritual death of the soul. Therefore a venial sin can become mortal.
2. Further, a movement in the sensuality before the consent of reason, is a venial sin, but after consent, is a mortal sin, as stated above (Question , Article , ad 2). Therefore a venial sin can become mortal.
3. Further, venial and mortal sin differ as curable and incurable disease, as stated above (Article ). But a curable disease may become incurable. Therefore a venial sin may become mortal.
4. Further, a disposition may become a habit. Now venial sin is a disposition to mortal, as stated (Article ). Therefore a venial sin can become mortal.
On the contrary
I answer that The fact of a venial sin becoming a mortal sin may be understood in three ways. First, so that the same identical act be at first a venial, and then a mortal sin. This is impossible: because a sin, like any moral act, consists chiefly in an act of the will: so that an act is not one morally, if the will be changed, although the act be continuous physically. If, however, the will be not changed, it is not possible for a venial sin to become mortal.Secondly, this may be taken to mean that a sin generically venial, becomes mortal. This is possible, in so far as one may fix one's end in that venial sin, or direct it to some mortal sin as end, as stated above (Article ).Thirdly, this may be understood in the sense of many venial sins constituting one mortal sin. If this be taken as meaning that many venial sins added together make one mortal sin, it is false, because all the venial sins in the world cannot incur a debt of punishment equal to that of one mortal sin. This is evident as regards the duration of the punishment, since mortal sin incurs a debt of eternal punishment, while venial sin incurs a debt of temporal punishment, as stated above (Question , Articles ,5). It is also evident as regards the pain of loss, because mortal sins deserve to be punished by the privation of seeing God, to which no other punishment is comparable, as Chrysostom states (Hom. xxiv in Matth.). It is also evident as regards the pain of sense, as to the remorse of conscience; although as to the pain of fire, the punishments may perhaps not be improportionate to one another.If, however, this be taken as meaning that many venial sins make one mortal sin dispositively, it is true, as was shown above (Article ) with regard to the two different manners of disposition, whereby venial sin disposes to mortal sin.
Reply to Objection: 1. Augustine is referring to the fact of many venial sins making one mortal sin dispositively.
2. The same movement of the sensuality which preceded the consent of reason can never become a mortal sin; but the movement of the reason in consenting is a mortal sin.
3. Disease of the body is not an act, but an abiding disposition; wherefore, while remaining the same disease, it may undergo change. On the other hand, venial sin is a transient act, which cannot be taken up again: so that in this respect the comparison fails.
4. A disposition that becomes a habit, is like an imperfect thing in the same species; thus imperfect science, by being perfected, becomes a habit. On the other hand, venial sin is a disposition to something differing generically, even as an accident which disposes to a substantial form, into which it is never changed.
Objection: 1. It would seem that a circumstance can make a venial sin mortal. For Augustine says in a sermon on Purgatory (De Sanctis, serm. xli) that "if anger continue for a long time, or if drunkenness be frequent, they become mortal sins." But anger and drunkenness are not mortal but venial sins generically, else they would always be mortal sins. Therefore a circumstance makes a venial sin to be mortal.
2. Further, the Master says ( Sentent. ii, D, 24) that delectation, if morose [*See Question , Article ], is a mortal sin, but that if it be not morose, it is a venial sin. Now moroseness is a circumstance. Therefore a circumstance makes a venial sin to be mortal.
3. Further, evil and good differ more than venial and mortal sin, both of which are generically evil. But a circumstance makes a good act to be evil, as when a man gives an alms for vainglory. Much more, therefore, can it make a venial sin to be mortal.
On the contrary Since a circumstance is an accident, its quantity cannot exceed that of the act itself, derived from the act's genus, because the subject always excels its accident. If, therefore, an act be venial by reason of its genus, it cannot become mortal by reason of an accident: since, in a way, mortal sin infinitely surpasses the quantity of venial sin, as is evident from what has been said (Question , Article , ad 1; Question , Article , ad 1).
I answer that As stated above (Question , Article ; Question , Article , ad 4; Articles ,11), when we were treating of circumstances, a circumstance, as such, is an accident of the moral act: and yet a circumstance may happen to be taken as the specific difference of a moral act, and then it loses its nature of circumstance, and constitutes the species of the moral act. This happens in sins when a circumstance adds the deformity of another genus; thus when a man has knowledge of another woman than his wife, the deformity of his act is opposed to chastity; but if this other be another man's wife, there is an additional deformity opposed to justice which forbids one to take what belongs to another; and accordingly this circumstance constitutes a new species of sin known as adultery.It is, however, impossible for a circumstance to make a venial sin become mortal, unless it adds the deformity of another species. For it has been stated above (Article ) that the deformity of a venial sin consists in a disorder affecting things that are referred to the end, whereas the deformity of a mortal sin consists in a disorder about the last end. Consequently it is evident that a circumstance cannot make a venial sin to be mortal, so long as it remains a circumstance, but only when it transfers the sin to another species, and becomes, as it were, the specific difference of the moral act.
Reply to Objection: 1. Length of time is not a circumstance that draws a sin to another species, nor is frequency or custom, except perhaps by something accidental supervening. For an action does not acquire a new species through being repeated or prolonged, unless by chance something supervene in the repeated or prolonged act to change its species, e.g. disobedience, contempt, or the like.We must therefore reply to the objection by saying that since anger is a movement of the soul tending to the hurt of one's neighbor, if the angry movement tend to a hurt which is a mortal sin generically, such as murder or robbery, that anger will be a mortal sin generically: and if it be a venial sin, this will be due to the imperfection of the act, in so far as it is a sudden movement of the sensuality: whereas, if it last a long time, it returns to its generic nature, through the consent of reason. If, on the other hand, the hurt to which the angry movement tends, is a sin generically venial, for instance, if a man be angry with someone, so as to wish to say some trifling word in jest that would hurt him a little, the anger will not be mortal sin, however long it last, unless perhaps accidentally; for instance, if it were to give rise to great scandal or something of the kind.With regard to drunkenness we reply that it is a mortal sin by reason of its genus; for, that a man, without necessity, and through the mere lust of wine, make himself unable to use his reason, whereby he is directed to God and avoids committing many sins, is expressly contrary to virtue. That it be a venial sin, is due some sort of ignorance or weakness, as when a man is ignorant of the strength of the wine, or of his own unfitness, so that he has no thought of getting drunk, for in that case the drunkenness is not imputed to him as a sin, but only the excessive drink. If, however, he gets drunk frequently, this ignorance no longer avails as an excuse, for his will seems to choose to give way to drunkenness rather than to refrain from excess of wine: wherefore the sin returns to its specific nature.
2. Morose delectation is not a mortal sin except in those matters which are mortal sins generically. In such matters, if the delectation be not morose, there is a venial sin through imperfection of the act, as we have said with regard to anger (ad 1): because anger is said to be lasting, and delectation to be morose, on account of the approval of the deliberating reason.
3. A circumstance does not make a good act to be evil, unless it constitute the species of a sin, as we have stated above (Question , Article , ad 4).
Objection: 1. It would seem that a mortal sin can become venial. Because venial sin is equally distant from mortal, as mortal sin is from venial. But a venial sin can become mortal, as stated above (Article ). Therefore also a mortal sin can become venial.
2. Further, venial and mortal sin are said to differ in this, that he who sins mortally loves a creature more than God, while he who sins venially loves the creature less than God. Now it may happen that a person in committing a sin generically mortal, loves a creature less than God; for instance, if anyone being ignorant that simple fornication is a mortal sin, and contrary to the love of God, commits the sin of fornication, yet so as to be ready, for the love of God, to refrain from that sin if he knew that by committing it he was acting counter to the love of God. Therefore his will be a venial sin; and accordingly a mortal sin can become venial.
3. Further, as stated above (Article , Objection ), good is more distant from evil, than venial from mortal sin. But an act which is evil in itself, can become good; thus to kill a man may be an act of justice, as when a judge condemns a thief to death. Much more therefore can a mortal sin become venial.
On the contrary An eternal thing can never become temporal. But mortal sin deserves eternal punishment, whereas venial sin deserves temporal punishment. Therefore a mortal sin can never become venial.
I answer that Venial and mortal differ as perfect and imperfect in the genus of sin, as stated above (Article , ad 1). Now the imperfect can become perfect, by some sort of addition: and, consequently, a venial sin can become mortal, by the addition of some deformity pertaining to the genus of mortal sin, as when a man utters an idle word for the purpose of fornication. On the other hand, the perfect cannot become imperfect, by addition; and so a mortal sin cannot become venial, by the addition of a deformity pertaining to the genus of venial sin, for the sin is not diminished if a man commit fornication in order to utter an idle word; rather is it aggravated by the additional deformity.Nevertheless a sin which is generically mortal, can become venial by reason of the imperfection of the act, because then it does not completely fulfil the conditions of a moral act, since it is not a deliberate, but a sudden act, as is evident from what we have said above (Article ). This happens by a kind of subtraction, namely, of deliberate reason. And since a moral act takes its species from deliberate reason, the result is that by such a subtraction the species of the act is destroyed.
Reply to Objection: 1. Venial differs from mortal as imperfect from perfect, even as a boy differs from a man. But the boy becomes a man and not vice versa. Hence the argument does not prove.
2. If the ignorance be such as to excuse sin altogether, as the ignorance of a madman or an imbecile, then he that commits fornication in a state of such ignorance, commits no sin either mortal or venial. But if the ignorance be not invincible, then the ignorance itself is a sin, and contains within itself the lack of the love of God, in so far as a man neglects to learn those things whereby he can safeguard himself in the love of God.
3. As Augustine says (Contra Mendacium vii), "those things which are evil in themselves, cannot be well done for any good end." Now murder is the slaying of the innocent, and this can nowise be well done. But, as Augustine states (De Lib. Arb. i, 4,5), the judge who sentences a thief to death, or the soldier who slays the enemy of the common weal, are not murderers.
We must now consider venial sin in itself, and under this head there are six points of inquiry:
(1) Whether venial sin causes a stain in the soul?
(2) Of the different kinds of venial sin, as denoted by "wood," "hay," "stubble" (1Co 3,12);
(3) Whether man could sin venially in the state of innocence?
(4) Whether a good or a wicked angel can sin venially?
(5) Whether the movements of unbelievers are venial sins?
(6) Whether venial sin can be in a man with original sin alone?
Objection: 1. It would seem that venial sin causes a stain in the soul. For Augustine says (De Poenit.) [*Hom. 50, inter. L., 2], that if venial sins be multiplied, they destroy the beauty of our souls so as to deprive us of the embraces of our heavenly spouse. But the stain of sin is nothing else but the loss of the soul's beauty. Therefore venial sins cause a stain in the soul.
2. Further, mortal sin causes a stain in the soul, on account of the inordinateness of the act and of the sinner's affections. But, in venial sin, there is an inordinateness of the act and of the affections. Therefore venial sin causes a stain in the soul.
3. Further, the stain on the soul is caused by contact with a temporal thing, through love thereof as stated above (Question , Article ). But, in venial sin, the soul is in contact with a temporal thing through inordinate love. therefore, venial sin brings a stain on the soul.
On the contrary it is written, (Ep 5,27): "That He might present it to Himself a glorious church, not having spot or wrinkle," on which the gloss says: "i.e., some grievous sin." Therefore it seems proper to mortal sin to cause a stain on the soul.
I answer that I answer that as stated above (Question , Article ), a stain denotes a loss of comeliness due to contact with something, as may be seen in corporeal matters, from which the term has been transferred to the soul, by way of similitude. Now, just as in the body there is a twofold comeliness, one resulting from the inward disposition of the members and colors, the other resulting from outward refulgence supervening, so too, in the soul, there is a twofold comeliness, one habitual and, so to speak, intrinsic, the other actual like an outward flash of light. Now venial sin is a hindrance to actual comeliness, but not to habitual comeliness, because it neither destroys nor diminishes the habit of charity and of the other virtues, as we shall show further on (II-II 24,10 II-II 133,1, ad 2), but only hinders their acts. On the other hand a stain denotes something permanent in the thing stained, wherefore it seems in the nature of a loss of habitual rather than of actual comeliness. Therefore, properly speaking, venial sin does not cause a stain in the soul. If, however, we find it stated anywhere that it does induce a stain, this is in a restricted sense, in so far as it hinders the comeliness that results from acts of virtue.
Reply to Objection: 1. Augustine is speaking of the case in which many venial sins lead to mortal sin dispositively: because otherwise they would not sever the soul from its heavenly spouse.
2. In mortal sin the inordinateness of the act destroys the habit of virtue, but not in venial sin.
3. In mortal sin the soul comes into contact with a temporal thing as its end, so that the shedding of the light of grace, which accrues to those who, by charity, cleave to God as their last end, is entirely cut off. On the contrary, in venial sin, man does not cleave to a creature as his last end: hence there is no comparison.
Objection: 1. It would seem that venial sins are unsuitably designated as "wood," "hay," and "stubble." Because wood hay and stubble are said (1Co 3,12) to be built on a spiritual foundation. Now venial sins are something outside a spiritual foundation, even as false opinions are outside the pale of science. Therefore, venial sins are not suitably designated as wood, hay and stubble.
2. Further, he who builds wood, hay and stubble, "shall be saved yet so as by fire" (1Co 3,15). But sometimes the man who commits a venial sin, will not be saved, even by fire, e.g. when a man dies in mortal sin to which venial sins are attached. Therefore, venial sins are unsuitably designated by wood, hay, and stubble.
3. Further, according to the Apostle (1Co 3,12) those who build "gold, silver, precious stones," i.e. love of God and our neighbor, and good works, are others from those who build wood, hay, and stubble. But those even who love God and their neighbor, and do good works, commit venial sins: for it is written (1Jn 1,8): "If we say that we have no sin, we deceive ourselves." Therefore venial sins are not suitably designated by these three.
4. Further, there are many more than three differences and degrees of venial sins. Therefore they are unsuitably comprised under these three.
On the contrary The Apostle says (1Co 3,15) that the man who builds up wood, hay and stubble, "shall be saved yet so as by fire," so that he will suffer punishment, but not everlasting. Now the debt of temporal punishment belongs properly to venial sin, as stated above (Question , Article ). Therefore these three signify venial sins.
I answer that Some have understood the "foundation" to be dead faith, upon which some build good works, signified by gold, silver, and precious stones, while others build mortal sins, which according to them are designated by wood, hay and stubble. But Augustine disapproves of this explanation (De Fide et Oper. xv), because, as the Apostle says (Ga 5,21), he who does the works of the flesh, "shall not obtain the kingdom of God," which signifies to be saved; whereas the Apostle says that he who builds wood, hay, and stubble "shall be saved yet so as by fire." Consequently wood, hay, stubble cannot be understood to denote mortal sins.Others say that wood, hay, stubble designate good works, which are indeed built upon the spiritual edifice, but are mixed with venial sins: as, when a man is charged with the care of a family, which is a good thing, excessive love of his wife or of his children or of his possessions insinuates itself into his life, under God however, so that, to wit, for the sake of these things he would be unwilling to do anything in opposition to God. But neither does this seem to be reasonable. For it is evident that all good works are referred to the love of God, and one's neighbor, wherefore they are designated by "gold," "silver," and "precious stones," and consequently not by "wood," "hay," and "stubble."We must therefore say that the very venial sins that insinuate themselves into those who have a care for earthly things, are designated by wood, hay, and stubble. For just as these are stored in a house, without belonging to the substance of the house, and can be burnt, while the house is saved, so also venial sins are multiplied in a man, while the spiritual edifice remains, and for them, man suffers fire, either of temporal trials in this life, or of purgatory after this life, and yet he is saved for ever.
Reply to Objection: 1. Venial sins are not said to be built upon the spiritual foundation, as though they were laid directly upon it, but because they are laid beside it; in the same sense as it is written (Ps 136,1): "Upon the waters of Babylon," i.e. "beside the waters": because venial sins do not destroy the edifice.
2. It is not said that everyone who builds wood, hay and stubble, shall be saved as by fire, but only those who build "upon" the "foundation." And this foundation is not dead faith, as some have esteemed, but faith quickened by charity, according to Ep 3,17: "Rooted and founded in charity." Accordingly, he that dies in mortal sin with venial sins, has indeed wood, hay, and stubble, but not built upon the spiritual edifice; and consequently he will not be saved so as by fire.
3. Although those who are withdrawn from the care of temporal things, sin venially sometimes, yet they commit but slight venial sins, and in most cases they are cleansed by the fervor of charity: wherefore they do not build up venial sins, because these do not remain long in them. But the venial sins of those who are busy about earthly remain longer, because they are unable to have such frequent recourse to the fervor of charity in order to remove them.
4. As the Philosopher says (De Coelo i, text. 2), "all things are comprised under three, the beginning, the middle, the end." Accordingly all degrees of venial sins are reduced to three, viz. to "wood," which remains longer in the fire; "stubble," which is burnt up at once; and "hay," which is between these two: because venial sins are removed by fire, quickly or slowly, according as man is more or less attached to them.
Objection: 1. It would seem that man could commit a venial sin in the state of innocence. Because on 1Tm 2,14, "Adam was not seduced," a gloss says: "Having had no experience of God's severity, it was possible for him to be so mistaken as to think that what he had done was a venial sin." But he would not have thought this unless he could have committed a venial sin. Therefore he could commit a venial sin without sinning mortally.
2. Further Augustine says (Gn ad lit. xi, 5): "We must not suppose that the tempter would have overcome man, unless first of all there had arisen in man's soul a movement of vainglory which should have been checked." Now the vainglory which preceded man's defeat, which was accomplished through his falling into mortal sin, could be nothing more than a venial sin. In like manner, Augustine says (Gn ad lit. xi, 5) that "man was allured by a certain desire of making the experiment, when he saw that the woman did not die when she had taken the forbidden fruit." Again there seems to have been a certain movement of unbelief in Eve, since she doubted what the Lord had said, as appears from her saying (Gn 3,3): "Lest perhaps we die." Now these apparently were venial sins. Therefore man could commit a venial sin before he committed a mortal sin.
3. Further, mortal sin is more opposed to the integrity of the original state, than venial sin is. Now man could sin mortally notwithstanding the integrity of the original state. Therefore he could also sin venially.
On the contrary Every sin deserves some punishment. But nothing penal was possible in the state of innocence, as Augustine declares (De Civ. Dei xiv, 10). Therefore he could commit a sin that would not deprive him of that state of integrity. But venial sin does not change man's state. Therefore he could not sin venially.
I answer that It is generally admitted that man could not commit a venial sin in the state of innocence. This, however, is not to be understood as though on account of the perfection of his state, the sin which is venial for us would have been mortal for him, if he had committed it. Because the dignity of a person is circumstance that aggravates a sin, but it does not transfer it to another species, unless there be an additional deformity by reason of disobedience, or vow or the like, which does not apply to the question in point. Consequently what is venial in itself could not be changed into mortal by reason of the excellence of the original state. We must therefore understand this to mean that he could not sin venially, because it was impossible for him to commit a sin which was venial in itself, before losing the integrity of the original state by sinning mortally.The reason for this is because venial sin occurs in us, either through the imperfection of the act, as in the case of sudden movements, in a genus of mortal sin or through some inordinateness in respect of things referred to the end, the due order of the end being safeguarded. Now each of these happens on account of some defect of order, by reason of the lower powers not being checked by the higher. Because the sudden rising of a movement of the sensuality in us is due to the sensuality not being perfectly subject to reason: and the sudden rising of a movement of reason itself is due, in us, to the fact that the execution of the act of reason is not subject to the act of deliberation which proceeds from a higher good, as stated above (Question , Article ); and that the human mind be out of order as regards things directed to the end, the due order of the end being safeguarded, is due to the fact that the things referred to the end are not infallibly directed under the end, which holds the highest place, being the beginning, as it were, in matters concerning the appetite, as stated above (Question , Articles ,2, ad 3; Question , Article ). Now, in the state of innocence, as stated in the I 95,1, there was an unerring stability of order, so that the lower powers were always subjected to the higher, so long as man remained subject to God, as Augustine says (De Civ. Dei xiv, 13). Hence there can be no inordinateness in man, unless first of all the highest part of man were not subject to God, which constitutes a mortal sin. From this it is evident that, in the state of innocence, man could not commit a venial sin, before committing a mortal sin.
Reply to Objection: 1. In the passage quoted, venial is not taken in the same sense as we take it now; but by venial sin we mean that which is easily forgiven.
2. This vainglory which preceded man's downfall, was his first mortal sin, for it is stated to have preceded his downfall into the outward act of sin. This vainglory was followed, in the man, by the desire to make and experiment, and in the woman, by doubt, for she gave way to vainglory, merely through hearing the serpent mention the precept, as though she refused to be held in check by the precept.
3. Mortal sin is opposed to the integrity of the original state in the fact of its destroying that state: this a venial sin cannot do. And because the integrity of the primitive state is incompatible with any inordinateness whatever, the result is that the first man could not sin venially, before committing a mortal sin.
Objection: 1. It seems that a good or wicked angel can sin venially. Because man agrees with the angels in the higher part of his soul which is called the mind, according to Gregory, who says (Hom. xxix in Evang.) that "man understands in common with the angels." But man can commit a venial sin in the higher part of his soul. Therefore an angel can commit a venial sin also.
2. Further, He that can do more can do less. But an angel could love a created good more than God, and he did, by sinning mortally. Therefore he could also love a creature less than God inordinately, by sinning venially.
3. Further, wicked angels seem to do things which are venial sins generically, by provoking men to laughter, and other like frivolities. Now the circumstance of the person does not make a mortal sin to be venial as stated above (Article ), unless there is a special prohibition, which is not the case in point. Therefore an angel can sin venially.
On the contrary The perfection of an angel is greater than that of man in the primitive state. But man could not sin venially in the primitive state, and much less, therefore, can an angel.
I answer that An angel's intellect, as stated above in the I 58,3; I 79,8, is not discursive, i.e. it does not proceed from principles to conclusions, so as to understand both separately, as we do. Consequently, whenever the angelic intellect considers a conclusion, it must, of necessity, consider it in its principles. Now in matters of appetite, as we have often stated (Question , Article ; Question , Article ; Question , Article ), ends are like principles, while the means are like conclusions. Wherefore, an angel's mind is not directed to the means, except as they stand under the order to the end. Consequently, from their very nature, they can have no inordinateness in respect of the means, unless at the same time they have an inordinateness in respect of the end, and this is a mortal sin. Now good angels are not moved to the means, except in subordination to the due end which is God: wherefore all their acts are acts of charity, so that no venial sin can be in them. On the other hand, wicked angels are moved to nothing except in subordination to the end which is their sin of pride. Therefore they sin mortally in everything that they do of their own will. This does not apply to the appetite for the natural good, which appetite we have stated to be in them (I 63,4; Question , Article , ad 5).
Reply to Objection: 1. Man does indeed agree with the angels in the mind or intellect, but he differs in his mode of understanding, as stated above.
2. An angel could not love a creature less than God, without, at the same time, either referring it to God, as the last end, or to some inordinate end, for the reason given above.
3. The demons incite man to all such things which seem venial, that he may become used to them, so as to lead him on to mortal sin. Consequently in all such things they sin mortally, on account of the end they have in view.
Summa Th. I-II EN Qu.88 a.3