1. Even in the absence of unusual emotional pressure, circumstances sometimes mitigate guilt (see S.t., 1–2, q. 73, a. 7). To be sure, emotion is present, but if it is not abnormally strong, the mitigation of guilt is not attributed to it. Sin in such cases is not a sin of weakness.
For example, one woman becomes a prostitute to satisfy her expensive tastes; she uses her income for self-indulgence. Another woman becomes a prostitute to provide better opportunities for her aged parents and illegitimate child; she works only two nights a week, to spend most of her time and energy caring for her family. The second woman’s sin is not a sin of weakness; strong emotion does not qualify the choice by which she commits herself to this way of life. But classical moral theology would say that in the second case circumstances diminish guilt. Since on my account of human action, the action is specified by all the intelligible factors which condition choice, I hold that the two sins differ in kind (cf. S.t., 1–2, q. 18, a. 6).
2. Sometimes wrongful behavior is nonvoluntary. Perhaps it results from coercion or from some factor which so affects an individual’s mind that he or she begins to act without choosing to do so and without even having had the possibility of so choosing (see S.t., 1–2, q. 6, a. 5; a. 7, ad 3). Since there is no consent at all in such cases, personal sin is excluded. This sort of wrongful behavior is not a sin of weakness either.
For example, Titus is physically dragged to an altar of pagan sacrifice, his fist held closed by a stronger person, then forced open to drop a bit of incense on the votive fire. Or Maximus is given a hypnotic drug, told to do the same thing, and does it without any choice at all. Or Paula is brought to the temple by force; she has every intention to resist, but when her throat is pricked with a knife, she winces and opens her hand—in this case knowing what she is doing, acting by spontaneous will, yet still without any choice at all.
If there is no choice, there is no morally significant human act—except insofar as the behavior or omission might be consequent upon some prior choice—and so there is no sin. Hence in all these cases of coercion one is not dealing with sin, and so there is no question of sin of weakness.
Cases in which circumstances mitigate guilt or wrongful behavior is nonvoluntary border on and are easily confused with sins of weakness. The remainder of this chapter is concerned with cases in which there are acts done through definite choices but under unusual emotional pressure. In such cases there is consent. But how full is this consent, if the sinner chooses to sin only after emotions become abnormally aroused? If weakness mitigates guilt, can it mitigate guilt to the point that a sin which otherwise would be mortal is no longer such?
3. There are four kinds of cases in which one sins through weakness in grave matter. These differ according to the relationship between emotion and choice involved in each.
Although one can sin through weakness in light matter, only sins of weakness in grave matter raise important pastoral questions, so only such sins will be analyzed here. Still, the analysis may be applied, mutatis mutandis, to sins through weakness in light matter.
4. First, sometimes emotion inhibits a person from making or carrying out a morally required choice. For example, sadness or fear can lead to hesitation and delay in regard to something which should be done. This constitutes a sinful omission through weakness. But as long as there is no definite choice to omit what one should do, the sin cannot be mortal.
Probably for this reason, the classical treatises on moral theology generally ignored sins of weakness of this sort. However, they are not insignificant. If the obligation which is not being satisfied is a grave one, a person unable to act because of emotional pressures has a responsibility to try to change the situation in ways which will make it possible to reduce and/or overcome the inhibiting emotions. For example, one might have an obligation to seek additional strength by natural or supernatural means: rest, the help of friends, medical advice, prayer, the reception of the sacraments, and so forth.
5. Second, weakness can render venial a sin which otherwise would be mortal. This plainly occurs if emotion distracts a person from the grave wrongness of a course of action (see S.t., 1–2, q. 77, a. 2). The emotion can be fear, anger, desire, hostility, or sadness. How distraction occurs was described in B above. The action here is akin to behavior which is nonvoluntary due to coercion or an abnormal state of mind, except that in the present case one does choose. One gives in to the emotion, but not until reflection has ceased to be sufficient for mortal sin. In other words, one chooses to do what one had realized would be seriously wrong, but only after one has stopped attending to its serious wrongness. Although such acts are not in themselves mortal sins, a person has a grave obligation to try to avoid situations in which emotional pressure will overwhelm reflection in this way.
One can understand the psychology of this type of sin of weakness if one considers examples in which someone chooses not to do an immoral act, with both moral motives (it is against conscience) and nonmoral motives for the choice. Perhaps the nonmoral motives have been purposely magnified in one’s thinking to reinforce one’s good purpose. However, as emotion mounts, attention is drawn to more of the appealing aspects of what one ought not to do and to fewer of the motives against it. At some point, it is possible to lose sight of the moral objection to the action to such an extent that one no longer is aware of the act as seriously wrong. One then chooses to do it, setting aside nonmoral motives. Sufficient reflection and full consent are not present together; hence, sins of weakness of this sort are venial.
For example, a firefighter on duty in a dangerous situation can be tempted to abandon his responsibilities and flee for safety. At first he resists this temptation partly by the thought that it would be dereliction of duty to give in to it and partly by the thought that his comrades will look down on him if he flees. As fear rises, a point can come when he forgets duty and chooses to flee, willing to accept shame rather than risk life. Again, a wife who is being abused can resist striking back due both to fear of the consequences and to an upright refusal to act vindictively, but choose revenge when anger blinds conscience: “I do not care if it hurts me worse than it does him; I’m going to get even with him for this!”
6. Third, sometimes strong emotion causes a person to act in a manner which is inconsistent with his or her previous upright character. Thrust into an unusual situation and perhaps lacking prior relevant experience, an individual freely chooses to do what is wrong, knowing it to be so. Isolated sins of weakness of this sort can occur in all sorts of matters and under the influence of every kind of emotion. The strength of the emotion and the unusualness of the situation mitigate guilt in such cases but do not eliminate it. If all the conditions for mortal sin are fulfilled, there is no reason to suppose that the sin is only venial (see S.t., 1–2, q. 77, aa. 6–8). Still, those who sin through weakness in this way very often repent quickly and sincerely.
For example, a student who previously has been honest is panicked by the prospect of a difficult examination, has an opportunity to purchase a stolen copy in advance, and decides to do it, although still considering the act gravely wrong. Again, a girl whose attitudes are in favor of life finds herself pregnant, is quite depressed but still realizes the gravity of abortion, and chooses that way to solve her problem. Again, a usually mild person is aroused to anger, realizes the evil of taking revenge, but freely chooses to do it.
7. Fourth, sometimes one sins through weakness in a way similar to the preceding in that a choice is made in a grave matter with sufficient reflection, but with this difference: that the sinner is not in an unusual situation and is not inexperienced. Rather, the act is part of a pattern of temptation, struggle, sin, repentance, and renewed temptation. Sin of weakness of this type can be called “quasi-compulsive.” Because it is common and seemingly intractable, sin of weakness of this kind most often presents a challenge to pastoral ministry. The remainder of this chapter is therefore devoted to its detailed consideration.
Scripture indicates that passion which leads to a sin one otherwise would not or might not commit does lessen guilt. God’s mercy is great because he knows human frailty (see Ps 78.38–39; 103.11–18). Peter’s denial of Jesus is a sin of weakness (see Mk 14.27–31, 66–72; Jn 13.38; 18.15–18, 25–27; 21.15–17).
Scripture also suggests that passion does not eliminate guilt, nor even always make venial the guilt of what would otherwise be a mortal sin. David’s sin clearly is one of weakness, of the third type. By his adultery and homicide, David merited death, for he had utterly spurned the Lord (see 2 Sm 12.13–14). St. Paul regards sins of the flesh—at least, some of them—as sins of weakness of the third or fourth types (see Rom 7.14–25); nevertheless, those who do the works of the flesh will not inherit the kingdom of God (see Gal 5.16–21).
The magisterium never has dealt in general with the question of the moral responsibility which remains when guilt is diminished by weakness. Condemned propositions suggest that one cannot suppose that sin of weakness would never be mortal (see DS 2151/1201, 2241–53/1261–73).
St. Thomas does treat clearly the questions whether sins of weakness, committed because of strong emotion, are diminished in guilt, and also whether they are still mortal sins. He holds that they are diminished in guilt, yet still can be mortal. In support of this view, Thomas refers to St. Paul: “While we were living in the flesh, our sinful passions, aroused by the law, were at work in our members to bear fruit for death” (Rom 7.5). Thomas also points out that crimes such as adultery and homicide often are done out of passion, and clearly are mortal sins.
Thomas considers cases in which strong emotion excludes deliberation and choice; he sets these cases aside. Where deliberation remains possible, one can set aside or block the emotional cause of temptation; what one pays attention to is within one’s own power. Thus, Thomas takes for granted that while moral responsibility remains, the sin remains mortal if the matter is grave. The only exception he allows is when strong emotion so controls reason that one no longer has power to resist; one is then temporarily insane (see S.t., 1–2, q. 77, a. 8).