209. Nature of vow. 1. A vow is defined: a promise made to God concerning a better good. Two things are required for a valid vow: the will of vowing and suitable matter.

a. A promise is the will of obligating oneself to doing or omitting something, and accordingly it introduces a true obligation. Wherefore a vow differs from a resolution conceived before God, which is the will of doing or omitting something, and therefore introduces no obligation. Hence omission of a resolution is not of itself a sin; but because of the motive of negligence or weariness on account of which it is omitted, it can accidentally be a venial sin.

b. It is of the essence of a vow that it be a promise made to God Himself; if some vow is made to saints, it is ordinarily to be understood that it is made to God in honor of the saints. But if someone vows only to a saint and in no way intends to promise anything to God, he does not make a vow properly so called, which by its nature is an act of latria, but elicits an act of dulia or hyperdulia (n. 136).

c. The faithful not rarely doubt whether they conceived a resolution or made a vow. In order that their doubt may be solved, it is not enough to attend to the word which they used: for even the word I promise often expresses only a resolution; but, according to St. Alphonsus, they are to be asked "whether then, when they made the vow, they thought that they would have sinned gravely or not, if afterward they had not satisfied it."² If the matter remains doubtful, it must be resolved that they made a resolution, because the obligation is not established.

d. For the value of a vow its acceptance on the part of God is required, for it is of the nature of a promise that it be accepted by him to whom the promise is made. But God at once accepts all promises made to Him which do not lack the due conditions: for unless God accepted promises made to Him, sacred Scripture would not urge the obligation of fulfilling the things which have been promised to God.³

2. A vow is an act of the virtue of religion, and indeed of latria: for by vow man offers a good work to God in order to honor and worship Him; but an act which is ordered to worship to be exhibited to God is an act of latria. And just as a vow is an act of the virtue of religion, so also the fulfillment of a vow pertains to the same virtue. Therefore a work furnished from vow has a twofold moral goodness.

The moral value of a vow is clear not only from this, that sacred Scripture exhorts to fulfillment of a vow (the places cited) and reports the example of St. Paul, who had made a vow,⁴ but also from the very nature of the thing: for a. works done from vow, beyond the goodness which they have from the object, put on the value of an oblation made to God and the merit of the virtue of religion; b. the one vowing offers a greater subjection toward God and a more perfect oblation; for by vow he obligates himself toward God and offers to God not only the thing promised in act, but through the obligation his very will; c. the tendency of the will into the good becomes more serious and firm through a vow; d. but if the execution of the vow is entangled with difficulties, not only is the fickle will strengthened, but in addition there is offered to the one vowing an occasion of showing fidelity and love toward God.⁵

¹ St. Thomas, II-II, q. 88, a. 1-12. St. Alphonsus, l. 3, n. 194-262. Suarez, De religione, tr. 6, l. 1-6. Thom. Sanchez, In praecepta decalogi, l. 4, c. 1-56. Lessius, De iustitia et iure, l. 2, c. 40. Th. Bouquillon, De virtute religionis (Bruges: Beyaert, 1880), pars II. I. Wirthmuller, Die mor. Tugend der Religion (Freiburg: Herder, 1881), p. 538 ff. Io. Reuter, Theologia moralis, pr. II, tr. 4. C. Kirchberg, De voti natura, obligatione, honestate etc. (Monasterii: Aschendorff, 1897).

² Praxis confess., c. 2, n. 25.

³ Cf. Eccl. 5:3, 4; Num. 30:3 ff.; Deut. 23:21.

⁴ Cf. Acts 18:18; 21:23 ff.

⁵ Cf. St. Thomas, II-II, q. 88, a. 6.

210. Division of vow. A vow is divided in many ways:

1. Into a private vow, which is made by the one vowing alone without the intervention of the Church, and a public vow, which is made by the authority and intervention of the Church.¹

2. A public vow is either solemn or simple, according as the Church by her authority accepts and confirms it as such, or accepts it not as solemn but only as simple; but before God each vow obligates essentially in the same way.

a. Solemn vows are: the vow of chastity made in the ordination of the subdiaconate, and the substantial vows which are made in religious orders, to which in some orders other solemn vows (accidental vows) are added; all remaining vows are always simple.

b. There is a celebrated controversy about what that is by which a solemn vow is constituted and differs from a simple one. It is certain that the solemnity of a vow has been constituted by the Church; therefore solemnity belongs to a vow not from its own nature but from ecclesiastical law. Moreover it seems certain that in the solemn vow itself, from the will of the Church, there is something which is not found in a simple vow. Each vow, solemn and simple, consists essentially in the handing over of the one vowing made to God and the Church, and in acceptance on the part of the Church. Now the specific note added by the Church to a solemn vow consists in such a handing over and acceptance as is of itself perpetual and irrevocable on each side, and which renders the one vowing incapable of certain acts contrary to the vows (of marriage, of possession, of contracting), unless the Church dispenses. Nor nevertheless is this note external to the vow, since the one vowing himself, from the will of the Church, consents that from his vow there follow both the aforesaid incapacities and a bond between himself and the Church or religious order which is indissoluble by the ordinary way.²

3. Into a personal vow, if some action of the one vowing himself, or omission of an action, is promised, as a vow of making a pilgrimage or of fasting; and a real vow, if directly some thing external to the one vowing is promised, but an action only so far as it is required for furnishing the thing, as a vow of giving alms; and a mixed vow, if each is promised at the same time, as a vow of making a pilgrimage and offering a candle.

4. Into a determinate vow, if the thing promised is accurately designated: I vow abstinence; and a disjunctive vow, if from several things proposed one thing to be furnished is promised, which can be determined at will: I vow fasting or alms.

5. Into a reserved and non-reserved vow, according as the power of dispensing or commuting belongs to the supreme pontiff alone, or also to other superiors.

6. Into a temporal and perpetual vow, according as it is promised to be observed only for a certain time or through the whole of life.

7. Into an express vow, if the internal promise is declared outwardly by words or other signs, as commonly happens; and a tacit vow, if the internal promise itself is not expressed outwardly, but nevertheless an action is knowingly posited to which a vow is annexed: thus the vow of chastity is made in reception of the subdiaconate.

An implicit vow must be distinguished from a tacit vow; thus he who vows religion implicitly vows chastity. An implicit vow differs from a tacit one in this, that an implicit vow is contained in that which is explicitly promised; a tacit vow is not contained in the action to which it is annexed, but the external action shows that a vow has been made interiorly.

8. Into a singular vow, which is made by a physical person, and a common vow, which is made by a moral person or by a community.

This division is taken from the subject making the vow, which in a common vow is the community as such, not the individual persons of the community.

9. Into an absolute and conditioned vow, according as something is promised simply or under a condition. A conditioned vow is divided into penal, if under the condition of fault a penalty to be inflicted is promised: if I blaspheme again, kneeling I shall recite the rosary; and non-penal, if something is promised merely under a condition: if I recover health, I shall undertake a pious pilgrimage.

Article Second. On the Conditions Required for a Vow

For vowing validly, some conditions are required on the part of the one vowing, others on the part of the matter.

¹ A public vow is sometimes defined in such a way that it is a manifest vow and is opposed not to private but to hidden. From this it is clear that a simple vow, which is opposed to solemn, according to the diverse definition of public, can be public and not public. Thus simple vows which are made in regular orders before profession are public (not private), because they are accepted by the Church; they are not public, because they are not manifest.

² Cf. Sanchez, In praecepta decal., l. 5, c. 1; Ballerini-Palmieri, II, n. 603; Lehmkuhl, I^11, n. 647.

211. On the part of the one vowing, for the essence and value of a vow there is required intention, deliberation, and perfect liberty.

Once these conditions have been declared, it will be clear that anyone who has reason and is not prohibited by positive law can vow. Therefore vows made after the completion of the seventh year are of themselves judged valid. Religious vows cannot validly be made before the sixteenth year of age, because before that time they are declared invalid by positive law.

1. Intention, or the will of promising and obligating oneself, is required, because each will pertains to a true promise.

a. A fictitious vow, or one made without the will of promising or of obligating oneself, is null; but a vow made with the mind of obligating oneself, but not of fulfilling it, is valid, but gravely or lightly illicit according to the nature of the matter.

b. The will of vowing or promising can indeed be distinguished by reason from the will of obligating oneself: for obligation is the essential and necessary effect of a promise; nevertheless, for this very reason, it is impossible that someone will to promise and not will to obligate himself.

212. 2. Perfect deliberation, namely that consideration of the thing and of the obligation which is required for a truly and perfectly human act: for no one is judged to obligate himself without sufficient deliberation. And this deliberation indeed is required for every vow, whether its matter is grave or light: for in every vow an obligation is undertaken; but for an obligation to be undertaken voluntarily there is required an act of mind and will that is perfectly human.

a. Therefore the vow of a child not yet perfectly in possession of reason is not valid even under light obligation, nor that of a man half-asleep or half-drunk. Nor is a vow made with complete ignorance or with only half-full knowledge of the obligation which it introduces valid; nor a vow made with only confused or general knowledge of some burden which is assumed. Nevertheless, in order that a vow be valid, consideration of the thing promised as to all its circumstances is not required, but knowledge of it as to its substance is sufficient.

b. In order that a vow be valid, prolonged and mature deliberation is not required. From defect of mature deliberation it not rarely happens that a vow is made imprudently; an inconsideration of this kind in making a vow furnishes a cause of dispensation or commutation, but it does not render the vow invalid.

c. If it is doubtful whether a vow was made with full deliberation, the vow does not obligate, since a doubtful obligation is none. But where the fact of the vow made is established, defect of full deliberation is not easily to be admitted.

213. On a vow made from error. a. It is not valid if the error is substantial, that is, either concerning the substance of the thing promised or concerning a substantial circumstance which, if it had been known, would have impeded the vow: for error of this kind removes the will of vowing, since there is no will where there is no knowledge. But it is valid if the error is accidental, that is, concerning an accidental circumstance which, if it had been known, nevertheless would not have impeded the vow: for error of this kind does not remove the will of vowing.

Therefore invalid is the vow by which someone promises to offer a chalice which he thinks is of copper, when it is of gold; by which someone promises a pilgrimage to a sanctuary which he thought was two hours distant, but is eight. But valid is the vow by which someone promises a pilgrimage to a place which he thought was three hours distant, but is four.

b. It is not valid if the error concerns the final or motive cause, because when the final cause is lacking, consent is lacking; but it is valid if the error concerns only an impulsive cause, namely one without which the vow would nevertheless be made, because full consent is present.

If someone promised a pilgrimage on account of health restored to his father, whom he later knows never to have been ill, he is bound to nothing. - If someone promised to go to a sanctuary primarily for honoring the Blessed Virgin, secondarily for visiting a friend there, he is bound to go, even if, at the time at which he promised this, the friend had already left that place.

c. Religious vows, however, are always valid, unless error bears upon the substance of the vows: for in making religious vows each person ought to have that intention which the religious state demands; but this demands that the one vowing will his vow to be valid, even if he is ignorant of some circumstance; for otherwise the religious state would not have that firmness which by its nature it ought to have.

214. 3. Perfect liberty, or free consent of the will, by which the one vowing wills himself to be obligated toward God to doing or omitting something.

On a vow made from fear. A vow made from fear which disturbs the use of reason, and therefore impedes the necessary deliberation, is not valid; but supposing the necessary deliberation, which even grave fear ordinarily does not impede,¹ these things are to be stated:

a. A vow made is valid: alpha. from grave fear which has arisen from an internal cause or from an external necessary cause; therefore a vow made in danger of life, whether from illness or from shipwreck, is valid, because the vow is freely chosen for escaping the imminent danger; beta. from grave fear which has arisen from an external free and just cause, as if one guilty of a crime must be subjected to a penalty unless he makes a determinate vow; gamma. from grave fear which has been impressed by an external free and unjust cause, but not for extorting a vow; therefore he is held by the vow who, in fear of death which robbers threaten, vows a pilgrimage if he should escape.

b. A vow made from grave fear which has been impressed by a free and unjust cause for extorting a vow is not valid, not only by ecclesiastical law, which in this case declares vows (at least solemn ones) void,² but also by the law of nature, not indeed because of defect of consent, but because God does not accept a coerced vow of this kind: for God cannot accept a promise which is extorted by unjust force, lest He seem to approve the injury inflicted upon the one vowing.³

There are those who probably extend this same thing even to light fear; and indeed the reason in each case is the same, provided it is established that fear was the true and sole cause of vowing. Therefore the vow of entering religion made by a girl is not valid, on the ground that her parents induced her to such a vow by importunate admonitions.

¹ For the same reason, a vow made in the heat of passion or devotion is ordinarily valid, even if the one vowing afterward repents of his vow, because an affection of this kind rarely impedes the necessary deliberation and liberty. Nevertheless, in these circumstances there is a sufficient reason for recurring to dispensation.

² C. Perlatum 1, De his, quae vi metusve causa fiunt (I. 40). Council of Trent, sess. 25, c. 19, De reg. et mon.

³ Ballerini-Palmieri, II, n. 609.

215. On the part of the matter, for the value of a vow it is required that it be possible, honorable, and concerning a better good.

1. Possible to the one vowing not only physically, but also morally: for no one can obligate himself to the impossible. But that is judged morally impossible which cannot be accomplished without great difficulty.

Therefore a. a vow of avoiding all venial sins, even semi-deliberate ones, is not valid, since this is impossible without a special privilege of God; b. a vow of avoiding all deliberate venial sins, whether in general or in a determinate species, is valid if it is made by a person who seriously strives for perfection; but in others, because of moral impossibility, this vow is null, unless it is a vow of avoiding deliberate venials of a certain species; c. a vow of avoiding all mortal sins is valid, because this is possible to all with the ordinary help of God: nevertheless it is not expedient that it be made by a frail person.

Whether a vow concerning a thing partly possible and partly impossible is valid depends upon the intention of the one vowing. If he intends to promise each part after the manner of one thing, he is held to nothing where he cannot fulfill the whole; but if he does not intend to vow after the manner of one thing, or if the intention of the one vowing is not established and the matter must be resolved from presumed intention, these things can be established:

a. If the matter is indivisible, or if in the possible part the reason of the vow is not preserved, he is held to nothing. Thus he who promised a Roman pilgrimage and cannot complete the whole way is held to nothing.

b. But if the matter is divisible, it is valid for that part which is possible, unless that part is accessory; hence he who vowed fasting and cannot abstain from meats is held to fasting as to the single meal.

You have another example in a vow of pilgrimage to be undertaken with bare feet, or of pilgrimage with reception of the sacraments. He who in the former vow cannot furnish the accessory is held to the principal thing, namely to the pilgrimage itself. In the other vow he who cannot make the pilgrimage is not bound to receive the sacraments; but if reception of the sacraments were the principal thing, he would be held to receive the sacraments at home.

216. 2. Honorable: for God is worshiped only by an action which is pleasing and acceptable to Him; but nothing is of this kind except what is morally good.

a. A vow concerning a vain or useless thing, for example of not going out of the house first with the right foot, is invalid. Likewise a vow concerning an indifferent thing, for example of not passing through a determinate street, is invalid, because it contributes nothing to divine worship. But if an indifferent thing from circumstances or from the end becomes morally good, it can be matter of vow.

b. To vow a vain or indifferent thing is a venial sin. To vow a lightly evil thing, according to some, is a venial sin; according to others, a mortal sin. To vow a gravely sinful thing, according to all, is a grave sin, because a grave injury is inflicted upon God.

The argument of those who say that a vow concerning a lightly evil thing is a grave sin seems to be convincing: for a vow of this kind supposes that an evil thing pleases God and is accepted by Him; but in these things there is contained irreverence toward God, which does not admit smallness of matter, because this is directly and immediately repugnant to His supreme holiness.

Whether a vow concerning a good thing, but evil from the end of the one vowing, is valid.

a. It is not valid if the evil end is the motive and total cause of the vow, which happens in two ways: when the vow is made for obtaining from God an illicit thing, and when it is made in thanksgiving for an illicit thing, as if someone vows alms for obtaining a favorable outcome of an unjust case, or if someone makes a vow because he has happily killed an enemy; for that end infects the whole vow and renders it evil and blasphemous.

b. A vow is valid if the evil end is an impulsive and partial cause of the vow, as if someone vows large alms before others indeed in honor of God, but also in order to be praised by men on that account. A vow of this kind is valid, because the evil end accompanies the vow, good in itself, only accidentally.¹

c. In like manner a vow made under an evil condition, which is not posited as the end of the vow, is valid; and this indeed not only if the condition in itself is a good thing which supposes an evil action, as if someone vows a pious work if he has escaped unharmed from a duel (to preserve life is a good thing, which he intends to obtain through the vow), but even if the condition is an evil thing, as if someone vows a pious work if he actually kills an enemy: for once the condition has been posited, it is honorable to fulfill the vow.²

¹ Ballerini-Palmieri, II, n. 621.

² St. Alphonsus, n. 206.

217. 3. Concerning a better good, that is, such that it does not impede a greater good; therefore the matter of a vow must be not only good in itself, but also better, not than any other good whatsoever, but than its opposite: for if the thing promised is a lesser good, the one vowing obligates himself to omitting a greater good in order to do a lesser; but this cannot be pleasing to God, who desires that man always do that which is better.¹ But it is not required that the thing promised absolutely be a better good, but it is sufficient that relative to the person vowing it be better than its opposite.

a. Hence a vow of marrying is not of itself valid, even if the vow is of taking a pious and poor woman, or one exposed to danger of incontinence, because for the one vowing celibacy is the greater good; nevertheless if marriage is necessary for someone, whether for removing scandal or because of danger of incontinence, for him it would be a better good and suitable matter of vow. Likewise, if someone has already proposed to take a wife, a vow of taking a poor woman in order to relieve her need is valid.

b. A vow of not vowing made absolutely is invalid, because it is better to vow than not to vow; but a vow of not vowing except with the license of the confessor is valid, because it is better to vow without danger of imprudence than with danger of imprudence. Yet if someone afterward should vow without consulting the confessor, the act of vowing would indeed be a sin, but the vow itself would be valid, unless he had also established this, that the future vow be invalid.²

Whether an action commanded can be matter of vow. - Nothing prevents a thing commanded from being able to be matter of vow; for on the part of the matter nothing else is required for a true vow except that it be a good thing, not impeding a better good; but a thing commanded is good and is better than its opposite, namely its omission, and the one vowing can add another obligation from religion to the obligation arising from the precept.

¹ Suarez, l. 2, c. 7, n. 2.

² Laymann, l. 4, tr. 4, c. 2, n. 5.