Section 5: The Obligation of Vows

1. Every valid vow entails the obligation of keeping the promise made to the best of one’s ability.¹

¹ Numb. XXX, 3 sqq.; Deut. XXIII, 21–23; Eccles. V, 3 sq.

“It pertains to the fidelity of a man,” says St. Thomas, “that he keep that which he has promised.... Above all man owes fidelity to God, both because of His overlordship and on account of benefits conferred, and consequently man is in a very special manner obliged to keep the vows he makes to God.”²

² Summa Theol., 2a 2ae, qu. 88, art. 3: “It pertains to the fidelity of a man that he render what he has promised. . . . Above all, however, man owes fidelity to God, both by reason of His dominion and by reason of the benefit received; and therefore man is especially obliged to fulfil vows made to God, for this pertains to the fidelity which man owes to God.”

“A vow obliges per se,” says Gury, “like a law or a commandment of the Church; that is to say, gravely in an important matter, and lightly in unimportant ones. For a vow is, as it were, a private law, which a man imposes upon himself.”³

³ Gury, Comp. Theol. Mor., I, n. 319: “A vow obliges of itself like a law or precept of the Church, and consequently gravely in grave matter and lightly in light matter; for a vow is, as it were, a certain private law which one imposes upon oneself.”

Failure to keep a vow involves faithlessness towards God and a violation of the reverence and respect due to Him by His creatures. It is a sin against the virtue of religion, and consequently a mortal sin, unless the matter involved is of no importance (parvitas materiae).⁴

⁴ For judging parvitas materiae in regard to vows, Noldin gives the following rule: “For judging smallness of matter in vows whose matter is promised after the manner of one whole, the matter omitted must be considered not absolutely but in relation to the whole thing promised, so that only a third or fourth part of the whole is to be considered a notable thing which cannot be omitted without grave fault. Thus one who promised to attend morning devotion for an entire month does not sin so gravely because he omits the devotion once or twice, even though the individual devotions, considered absolutely (if they last half an hour), constitute grave matter, but because he omits eight or ten attendances.” (Summa Theol. Mor., Vol. II, p. 233).

In gauging the obligation involved in a vow, the first and most important thing to be considered is the intention.

“Ordinarily,” says Fr. Slater, “it will be presumed that in a grave matter, such as the Church considers to be sufficient for a precept to bind under mortal sin, a vow also binds under pain of grave sin, for the intention of him who took the vow is presumed to accommodate itself to the matter. Nothing, however, prevents him from limiting the obligation of a vow even in a grave matter, so that transgressions of it will be only venial sins, if he expressly intends it.”⁵

⁵ A Manual of Moral Theology, I, 249.—St. Thomas, Summa Theol., 2a 2ae, qu. 88, art. 3, ad 3: “The obligation of a vow is caused by one’s own will and intention.”—Gury, Comp. Theol. Mor., I, n. 319: “A vow obliges according to the intention of the vower, if he determines the quantity of the obligation in the act of vowing, so that he can bind himself under light obligation only in matter however grave. The reason is that, just as a legislator or superior can in grave matter bind under light obligation only, so also one who vows concerning a grave thing can impose upon himself a light obligation only. He cannot, however, conversely bind himself gravely in a light matter, because light matter is not capable of a grave obligation.”

In case of doubt it may be presumed that the obligation binds sub gravi. If the matter of the vow is something commanded by law (e. g., chastity, temperance), failure to keep it would be a twofold sin, either mortal or venial according as the law in question obliges under pain of mortal or of venial sin.

2. If it is either physically or morally impossible to keep a vow, the latter ceases to bind; nor is he who made it obliged to do something which is a mere accessory to the substance of the vow, even if this were possible. If the matter is capable of being divided, as said above, the vow should be lived up to as far as possible.⁶ Fr. Slater illustrates this rule as follows: “One who should vow to fast for a week, if he found this impossible, would not be excused from fasting on the days that he could do so. But if he had vowed to build and decorate a church, and afterwards found this to be impossible, he would not be bound to build a portion of it, nor to decorate some other church.”⁷

⁶ St. Thomas, Summa Theol., 2a 2ae, qu. 88, art. 3, ad 2: “If that which someone has vowed is rendered impossible by any other cause, he ought to do what is in his power, so that he may at least have a ready will to do what he can. Hence one who has vowed to enter a certain monastery ought to make every effort he can to be received there. And if his intention was principally to bind himself to entrance into religion, and as a consequence he chose this religious institute or this place as though more suitable to him, he is bound, if he cannot be received there, to enter religion elsewhere. But if he principally intended to bind himself to this religious institute or this place because of a special pleasure in this institute or place, he is not bound to enter another religious institute if they are unwilling to receive him there.”—Cfr. Gury, Comp. Theol. Mor., I, n. 315.

⁷ A Manual of Moral Theology, Vol. I, p. 251.

If a vow is unlimited as to time, it should be kept as soon as possible and not be postponed without grave reason, especially if, through carelessness or later impossibility of fulfilment, the delay is likely to result in complete nonfulfilment or to render the object of the promise illusory. A merely temporary impossibility does not annul the obligation, which, on the contrary, revives as soon as the obstacle is removed. The term assigned for the fulfilment of a vow should be adhered to, but if it has passed, the neglected duty cannot be validly complied with later.⁸ Violation of a permanent vow (e. g., of virginity) does not annul the obligation,⁹ but may become an im- portant inducement for the ecclesiastical superior to grant a commutation or a dispensation.

⁸ Deut. XXIII, 21 sqq.—St. Thomas, Summa Theol., 2a 2ae, qu. 88, art. 3, ad 3: “If it is in the intention and will of the vower to bind himself to render it immediately, he is bound to render it immediately; but if for a certain time or under a certain condition, he is not bound to render it immediately, yet neither ought he to delay beyond that to which he intended to bind himself.”—Gury, Comp. Theol. Mor., I, 321: “Question: What delay is to be considered grave? Answer: 1. Every delay of a gravely binding vow which is attached to a determined time is grave of itself, as is a vow of fasting on a certain vigil, etc., because when the time has elapsed, the obligation of the vow ceases and cannot be compensated. 2. But if no determined time was fixed, or if it was fixed only to urge execution of the vow, a notable delay in a grave matter will be a grave sin; what delay is notable, however, must be judged from the nature of the thing promised, from the end, and from other circumstances. Generally speaking, less delay is required for a grave sin where there is danger of forgetfulness or inability, or a notable diminution of the vow, as in those things which are undertaken for one’s whole life.”—Ibid., n. 323: “A vow indeterminate as to the cessation of time, for example, concerning a daily rosary or a fast to be made every Saturday, obliges perpetually unless something else is gathered from the circumstances. In doubt whether the vow is temporary or perpetual, or for a month or a year, the minimum must be held.”

⁹ St. Thomas, Summa Theol., 2a 2ae, qu. 88, art. 3, ad 2: “If [he who vowed to enter a certain monastery ] falls into an impossibility of fulfilling the vow through his own fault, he is bound in addition to do penance for his own past fault, just as a woman who vowed virginity, if she is afterward corrupted, not only ought to preserve what she can, namely perpetual continence, but also to repent for what she lost by sinning.”

Conditional vows take effect only after the postulated condition has set in. Arbitrarily and maliciously to prevent the condition from being verified, either by intrigue, force, or malice, is forbidden.¹⁰

¹⁰ St. Thomas, Summa Theol., 2a 2ae, qu. 88, art. 3, ad 3.—Busembaum, Medulla Theol. Mor., l. III, tr. 2, c. 3, dub. 4, n. 11: “Conditional vows do not oblige when the condition ceases, even if the vower himself was the cause that the condition was not fulfilled, provided he did not prevent it by deceit, force, or malice; for example, you vowed a pilgrimage if Peter approves it, and then you send someone to persuade him not to approve it; therefore, when he does not approve it, you are not bound.”

A personal vow binds him who makes it and no one else. A vow conditioned upon the consent of another takes effect only after that consent has been given.

A “real” vow (votum reale) falls upon the heirs of him who made it, if the matter involved is one of justice, but it never obliges ultra vires haereditatis. The legal obligations of a testator sub titulo iustitiae always take precedence of any vows he may have made.¹¹

¹¹ H. Busembaum, S.J., Medulla Theol. Mor., l. III, tr. 2, c. 3, dub. 4, n. 5–9; Gury, Comp. Theol. Mor., I, n. 323.

In regard to doubtful vows, Archbishop Simar lays down the following rules: a) If it is doubtful whether a vow has been made, it may be regarded as not binding. The same rule holds with regard to any circumstance of which it is uncertain whether or not it formed part of the vow.

b) If insuperable doubts arise as to the validity of a genuine vow, or if it is uncertain whether the vow has been fulfilled or not, the obligation remains.

c) If there is doubt as to the qualities or extent of the obligation incurred, this doubt must be solved with due regard to current views regarding such matters, and according to the commonly accepted meaning of the terms employed.¹²

¹² H. Th. Simar, Lehrbuch der Moraltheologie, 3rd ed., p. 284; cfr. Göpfert, Moraltheologie, Vol. I, 6th ed., p. 323.

The interpretation of vows is subject to the same rules as the interpretation of laws.¹³ The decisive factors are: the intention, the nature of the object, and common sense. Consequently, if a man has vowed to make a donation for some religious or charitable purpose, without determining the amount, he may give as much or as little as he pleases, provided, of course, the gift be not so small as to appear a mockery of God rather than the fulfilment of a vow. If one has vowed to give something without reference to quality, it is sufficient to follow common usage or custom. A vow unlimited as to duration (for instance, to recite the Rosary every day) is regarded as perpetual, unless the circumstances of the case indicate a contrary intention.

¹³ See this Handbook, Vol. I, pp. 177 sqq.; cfr. Noldin, Summa Theol. Mor., Vol. II, pp. 238 sq.

On account of the responsibility and obligation involved, a Catholic should never make a vow without having consulted his father confessor or some other prudent and experienced guide.

Priests should exercise great caution in regard to vows, especially those intended to be perpetual or to last for a long time. In many cases it may be advisable to impose a period of probation, say one year, after the expiration of which the vow may be renewed.

The so-called pledge (to abstain from intoxicating drink) is no vow, but merely a good resolution made known to a priest, and hence does not oblige sub gravi. Sabetti rightly admonishes the clergy to “use great prudence and discretion in receiving such promises.”¹⁴

¹⁴ Comp. Theol. Mor., § 150; cfr. Irish Eccl. Record, May, 1883, pp. 338 sqq.

READINGS.—Thos. Slater, S.J., A Manual of Moral Theology, Vol. I, pp. 249 sqq.—F. X. Linsenmann, Lehrbuch der Moraltheologie, pp. 333 sqq.—J. B. Wirthmüller, Die moralische Tugend der Religion, pp. 562 sqq.—J. B. Ferreres, S.J., Comp. Theol. Mor., Vol. I, 9th ed., pp. 277 sqq.—Sabetti-Barrett, Comp. Theol. Mor., 28th ed., pp. 233 sq.—H. Noldin, S.J., Summa Theol. Mor., Vol. II, pp. 231 sqq.—F. A. Göpfert, Moraltheologie, Vol. I, 7th ed., pp. 476 sqq., 481 sq.—E. Müller, Theol. Mor., Vol. II, pp. 178 sqq.—A. Lehmkuhl, S.J., Theol. Mor., Vol. I, pp. 328 sqq.