Summa summae S. Thomae, Tomus II

§ I.

Whether every act joined to an omission, and incompatible with the observance of the precept that is omitted, is a sin, and of what species?

I suppose from the preceding treatise on Human Acts, dissert. I, a. 2, that the sin of omission can exist without any act which is of its essential character, yet not without every act which is the cause or occasion of it. There can also intervene an act only concomitantly, and which is not the cause or occasion of it,

I say 1° : Every act, though good from its object, which is the cause or occasion of the omission of an act commanded, is vitiated by the very omission and becomes evil. But an act which is not the cause or occasion of the omission, but stands to it only concomitantly, although it be incompatible with the commanded act, unless it be evil from elsewhere, is not a sin, nor is vitiated by the omission. Whence, if anyone out of affection for study omit Mass, the study is evil; but if anyone, after a firm resolution to omit Mass, lest he remain idle, studies, the study is not a sin.

The first part is clear : 1° Because to posit the cause or occasion of sin is to consent to sin and will it indirectly. But to consent to sin, and will it even indirectly, is sin, Rom., I, 32. 2° Because by the same precept both the omission is forbidden and the act which is its cause or occasion; thus, v. g., the affirmative precept of hearing Mass includes virtually the negative precept forbidding all things impeding the hearing of Mass.

The second part also is clear : because, since this act is supposed evil neither from itself nor from its circumstances, it can have no malice except from the omission. But it can have none from an omission of which it is not the cause or occasion, but toward which it stands only per accidens and concomitantly. Therefore.

If you say this act is done at an undue time, I answer : The supposition being made that one has previously efficaciously determined himself to omit the commanded act, v. g., Mass, then study does not occur at a time formally and privatively undue, but materially only; because then study is not forbidden by reason of itself, but by reason of the omission of Mass, of which it is not the cause or occasion. Whence it is better then to study than to remain idle.

Hence you will infer that persons playing at the time of Mass with one who has previously firmly resolved not to hear Mass do not sin, since this play, as standing only concomitantly to the omission of Mass, is not a sin, and thus the fellow-players do not share in the sin of the other : otherwise, for the opposite reason, it would have to be said if he omitted Mass on account of the play.

Moreover, understand the second part of the conclusion of an act which stands thus concomitantly to the omission, so however that it does not take away the power of fulfilling the precept, in case there be place and hope of retracting the evil resolution; for then although this act would stand consequently or only concomitantly to the first omission, it would nevertheless stand antecedently and causally to subsequent omissions, in case he changed his will, whose change is supposed to have place and hope present. Nay he would commit a new sin distinct from the omission, because not only is disobedience to a precept a sin, but especially to take away from oneself the possibility of fulfilling it; which is a sign of a heart hardened.

Hence you will infer that a cleric sailing, who after the impious resolution of not reciting the Hours throughout a long voyage throws his Breviary into the sea, commits besides the omission a distinct sin to be declared in confession, on account of the impossibility which he voluntarily contracts of fulfilling the precept, while there is place and hope, on account of the length of time, of retracting the evil resolution.

I judge the same of him who, after a firm resolution not to keep the vow of chastity, takes a wife; the same of him who, after a firm will not to restore what belongs to another, squanders it : and of other like cases. Otherwise of him who, after an efficacious resolution not to hear Mass, gives himself to sleep at the time of Mass drawing near, because it is unlikely that in so brief an interval he changed his mind; and accordingly sleep is not held to take away the moral power of hearing Mass, but to suppose it taken away.

I say 2° : Although an act good or indifferent of itself, which is the cause or occasion of a culpable omission, becomes evil, nevertheless the common opinion is, against the few, that it is not evil with any other malice than that of the omission, and thus need not necessarily be declared in confession; so that he who omitted Mass on account of study or play suffices if he say he omitted Mass.

The reason is, because, as the will of omitting is not a sin distinct either in species or number from the omission itself (for the will of omitting stands to the omission as the interior act to the exterior, which adds no goodness or malice to the interior), so neither does the act which is the cause or occasion of the omission, since it is evil precisely inasmuch as it includes the will of omitting.

It is confirmed. The omission and the act which is its cause or occasion are forbidden by the same precept, as has been said; for the law which commands hearing Mass, v. g., includes the negative precept forbidding the positing of an act impeding the hearing of Mass. Therefore both act and omission are against the same virtue of religion.

§ II.

At what time is the sin of omission made?

The question concerns the case in which someone, while the precept presses, is impotent to fulfill it, v. g., foreseeing in the morning the obligation of hearing Mass, made himself drunk. It is asked whether he sins with the sin of omission when he made himself drunk, or when the time of hearing Mass runs.

I say : The sin of omission is made at both times : inchoatively and as regards the affect, when the cause is posited; consummately and as regards the effect, when the time of fulfilling is present; provided however the omission remain voluntary in its cause.

The first part is admitted by all, and is clear; because sin begins then, when the will of sinning begins. But he who voluntarily posits the cause of a culpable omission wills at least indirectly the culpable omission itself. Therefore.

The second part is proved, 1° by overturning the foundation of the opposite opinion. The sin of omission consists in the voluntary privation of the act owed. But while the omission de facto occurs, then there is given the privation of the act owed, and such privation is sufficiently voluntary to be sinful. Therefore. — The first part of the minor is evident. — The second is proved, concerning which is the difficulty. For anything to be sin in itself, it suffices that in its cause it be voluntary. But a contingent omission, v. g., in sleep or drunkenness, is voluntary in its cause; for we suppose that the sleep or drunkenness was freely posited. Therefore. — The major is proved, 1° by various examples. Thus nocturnal pollution, although not formally free and voluntary in itself, is a sin, because it is voluntary in its cause, namely by an impure thought or touch. Thus homicide perpetrated in drunkenness by him who foresaw it is sinful in itself, because it is voluntary in its cause, as St. Thomas teaches, IIa IIae, q. 150, a. 4, c. Thus acts of sin committed from vincible ignorance are sinful in themselves, although involuntary in themselves, namely unknown, but voluntary only in their cause, namely the ignorance. Therefore. 2° If for formal sin there were always required that it be voluntary in itself, and the voluntary in cause did not suffice, no homicide, no pollution — say the same of many others — would be a sin in itself; because while they de facto happen they are no longer in the power of the slayer or of the one polluting himself.

2° The sin of omission consists in the voluntary cessation from the act owed. But before the time at which the obligation of the precept runs, the act is not owed. Therefore. As therefore, when one wishes to steal, before he takes what is another's, the completed sin of theft does not yet exist; so, when one wishes to omit, before he omits, the completed sin of omission does not yet exist.

It is confirmed. An actual omission must be accused in confession, no otherwise than an exterior act, and thus runs the common practice of the faithful and of confessors. Therefore it is sinful.

Obj.: From our opinion it follows that a man in his sleep could merit and confect the sacraments, since no greater liberty is required for meriting and for confecting the sacraments than for sinning. But each is unfitting. Therefore.

I answer. to the first, that it is not unfitting for a man in his sleep to merit by continuation of merit compared to his vigilance, especially if the effect follow per se from the cause freely willed, or be formally intended, as appears in the martyr, who in the instant of death, while not master of himself, merits the aureole of martyrdom. We deny however that he can validly confect a sacrament, not through defect of sufficient liberty, but because Christ, according to the common sense of the Church, instituted and willed the sacraments to be confected by a man master of himself, and with due moral certitude concerning the matter, partly on account of the reverence of the sacrament, partly on account of the danger of many inconveniences which would otherwise arise. Add that the words of one sleeping are not formal words, through defect of signification, but material words, as in a parrot uttering them.

You will ask 1° whether there ought to be imputed to him who voluntarily and culpably posited the cause all the sinful omissions and commissions following from it.

I answer. and let it be a general rule : To him who voluntarily and culpably posited the cause are imputed, as regards guilt and affect, all the sinful omissions and commissions which he foresaw, or ought and could humanly have foreseen to follow from such a cause; because by this very fact they are voluntary in their cause. But

You will ask 2° when one is held to have foreseen, or to have been able and bound humanly to foresee, sinful omissions and commissions, that they be imputed to him as fault.

I answer. in several ways : 1° when they follow per se or usually from such a cause; 2° when one sees similar things happen in others of like complexion; 3° when the precepts to be fulfilled draw immediately near.

Thence you will be able to gather various consequences for practice.