Question VIII: Whether, and how, a custom of swearing is evil

The habit of swearing is not in itself a sin distinct from the very acts of swearing that are frequent. For it is the very act frequently repeated, as Aristotle teaches in 2 Ethics; but the effect of the acts, which is a certain habit of swearing, resulting from frequently repeated acts, inclines to evil, and so far is vicious; nevertheless it cannot be a sin, which ought to be found in the acts. So Soto lib. 8. de Iustitia, quaest. 2. art. 3. concl. 7. Suarez lib. 3. cap. 6. Sanchez lib. 3. cap. 5. num. 4. Yet that habit of swearing can be a proximate occasion of mortal sins, and for that reason can place one in a state of mortal sin. The question, therefore, is when this happens.

¶ The first opinion is that any habit whatsoever of swearing, even if it is not one of lying under oath, makes one guilty of mortal sin. So Soto de cavendo iuramentorum abusu, cap. 11. Sayrus lib. 5. cap. 9. num. 8. where he says that such persons are not to be absolved unless they propose to root out the habit.

The second opinion is that a habit of swearing joined to a habit of lying without an oath places one in danger in this state, and so far is one mortally wounded. So Gregory of Valencia 2. 2. disp. 6. quaest. 7. puncto 3. Petrus Ledesma 2. Tomo summae, tract. 11. cap. 5. dub. 5. dicto 2.

The third opinion is that such a habit of swearing is [evil] when one swears with attention to the oath, but not to the truth or falsity of the thing sworn; but otherwise when one attends to neither, and the emission of the oath outruns the full attention of reason. So Azorius Tom. 1. lib. 11. cap. 3. quaestio 3. and Bassaeus V. Iuramentum 4.

The fourth opinion is that of Sanchez lib. 3. cap. 5. a num. 9. where he says five things. First, that a habit of swearing with due attention to the truth of the thing sworn does not place one in a state of mortal sin; and in this part he has as assertors Scotus 3. dist. 39. quaest. unic. art. 1. Gabriel quaest. 2. art. 1. notab. 2. Sayrus lib. 5. cap. 5. Medina lib. 1. summae, cap. 14. §. 4. Lopez p. p. Instruct. cap. 25. et cap. 42. SECOND, Suarez says that neither a habit of lying joined to a habit of swearing what is true is mortal. For this he also cites Suarez lo. co citato, num. 6.

THIRD, he says that a habit of swearing indifferently, whether what is true or what is false, is mortal. He also cites Suarez cap. 6. num. 6. et 8. Petrus Ledesm. 2. Tomo, tract. 11. cap. 5. dub. 4. Valentia loco cit. Vega loco citato.

FOURTH, he says that when there is a habit of swearing inattentively regarding the truth of the thing sworn, it is mortal. He also cites Aragon 2. 2. quaest. 89. art. 3. dub. ultimo, Suarez loco cit. num. 9. Petrus Ledesma cap. 5. dub. 4. Azorius Tom. 1. lib. 11. cap. 3. quaestio 3.

FIFTH, the same must be said when the habit is of swearing without attention, whether one swears or not, against the third opinion; and he also cites Suarez num. 8.

AS REGARDS St. Bonaventure, in the following assertions I shall state what he thought about this matter.

I ASSERT first, that the habit of swearing is then lethal when it is a proximate occasion of mortal sin, namely, of swearing what is false, or rash, according to what was said in the preceding question.

It is PROVED from St. Bonaventure in 3. dist. 39. quaest. 3. in fine, and serm. 3. in Decal. from that text of Ecclesiasticus 23: Let thy mouth be not accustomed to swearing, for there are many falls in it. A man that sweareth much shall be filled with iniquity.

HENCE it follows that not every habit whatsoever of swearing is of this kind, for instance swearing what is true out of slight necessity, or small reverence. For these are habits evil only venially. It is proved from Scotus. For a habit draws its whole malice from the acts from which it is generated; and so it cannot be worse than the acts themselves. If, therefore, the acts are venial, such also will be the habit.

I ASSERT next, that a habit of swearing, through inattention to a known false matter, in such a way that one deliberates only about the simple lie, but the oath slips out besides, is mortal: because that inattention, once known and foreseen, becomes voluntary in whatever act; and so far it is mortal perjury. And this is what St. Bonaventure says quaest. 3. in corpore: if one deliberates about the saying only, and not about the oath added over it, it can be venial, but it comes very near to the mortal; that is, if one deliberates only to speak a lie in his saying, not attending that he confirms it by an oath, it can be venial, namely a simple lie; yet it can become mortal, if that heedless slip of an oath passes into a habit that is known, or is foreseen.

It is PROVED, because inattention, whether regarding the oath, or regarding the truth, is a grave defect of judgment, as we said in question 7, and it exposes one to the danger of perjury, which according to St. Bonaventure in the place there cited, and others, is a grave injury done to God.

THEREFORE if a habit involves the danger of grave lapses against the oath, according to what was said in questions five and the following, it will also be a habit gravely evil. Because such a habit is such as are the acts produced by it: but if the acts produced, or resulting from it, are venial from the defect of some reverence, it will itself also be lightly evil, as St. Bonaventure indicates quaest. 3. ad 3.

HENCE it follows that one is bound to root out a habit that is the cause of perjury; otherwise one sins by the sin of omission. Therefore absolution must be denied to him if he does not propose to extirpate a habit gravely evil; not so the man who abounds in a light habit, who is improperly a perjurer, with judgment failing, or justice failing but lightly.