(b) If the vower has not determined the relation between the items of the vow, the presumption as a rule favors coalescence in real vows, non-coalescence in personal vows (as in the examples of a vow to give fifty cents daily and of a vow to say a Hail Mary every day). But there are exceptions, as when one vows to give a small alms every Saturday in honor of the Blessed Virgin, for the chief intention in this case may be to show respect to the Mother of God and not to give a certain amount to the poor.
2213. The Time When a Vow Obliges.—(a) A negative vow (e.g., not to drink certain intoxicants) obliges at once and always (see 371).
(b) An affirmative vow to which the vower has annexed a time for fulfillment obliges at the time determined. If the time was intended as a principal circumstance (e.g., a vow to say the Rosary on the Feast of the Assumption), the vow ceases with that time, even though performance was culpably neglected; but if the time was intended only as a secondary circumstance (e.g., a vow to go to confession next week made by one who needs it badly), the vow continues in force even after the time set has elapsed without fulfillment (see 468 sqq.). Anticipation of fulfillment on account of inability to fulfill at the time appointed in the vow, is not necessary, unless the vow was attached to a certain space and cannot be fulfilled in the latter part of this space; for example, if one has vowed to say the Rosary today and foresees that the whole afternoon will be occupied, one should say the Rosary in the forenoon (see 470, 471).
(c) An affirmative vow for which the vower has fixed no special time should be accomplished as soon as this can be conveniently done, for such is the rule in every absolute promise, and, moreover, no better time for fulfillment can be assigned; “When thou hast made a vow to the Lord thy God, thou shalt not delay to pay it, because the Lord thy God will require it. And if thou delay it shall be imputed to thee for a sin” (Deut., xxiii. 21).
2214. Delay in Fulfilling Vow.—Sin may be committed by delaying to keep a gravely obligatory vow for which no date was set.
(a) There is no sin if the delay is reasonable in view of the subject-matter of the vow (e.g., to put off a Rosary or fast for two or three days, a pilgrimage of 50 miles for a week, a pilgrimage of 1000 miles for several months, etc.) or of the circumstances (e.g., if one has to delay entrance into religion until one has better health or has closed up a business).
(b) There is venial sin if the delay is unreasonable but does not notably diminish what is promised or endanger its fulfillment. Thus, a Rosary, a fast, or a pilgrimage is as good next year as this year, and, apart from danger of forgetting or omitting, no lapse of time seems to constitute a notable delay in respect to such obligations.
(e) There is mortal sin if the delay is unreasonable and notably depreciates what is promised or notably endangers performance of the vow. Thus, to put off the fulfillment of a vow to enter religion lessens the value of the thing promised, if one waits until old age; it imperils the promise, if one remains in the world for several years exposed to the danger of losing vocation. Moralists hold that three or four years would be a considerable delay in reference to a vow to enter religion.
2215. The Person Obliged to Fulfill a Vow.—(a) A personal vow obliges only the vower, because by its nature a vow is a law which one imposes on oneself (see 463, 1696, 188). But vows taken by a city or community may be obligatory on the subjects in virtue of law, and vows taken by ancestors may oblige posterity in virtue of lawful and obligatory custom. (b) A real vow (and a mixed vow as to the part that is real) obliges also the heirs, for this kind of vow is a debt of the vower’s estate (see Canon 1310). The obligation of the heirs is one, not of religion, but of justice, and they are not held beyond the resources of the estate.
2216. The Manner of Fulfilling a Vow.—(a) As to Internal Disposition.—It is not necessary that one have at the time of fulfillment the purpose of fulfillment, provided there is no intention exclusive of that purpose, for the vow binds one only to do what was promised (cfr. 477). Hence, if one has vowed to hear Mass and then hears a Mass out of devotion, not thinking of the vow, one may take this assistance at Mass as a satisfaction of the vow.