Summa Theologica, by St. Thomas Aquinas, [1947], at sacred-texts.com
We must next consider the impediments which supervene to marriage. We shall consider (1) the impediment which affects an unconsummated marriage, namely a solemn vow: (2) the impediment which affects a consummated marriage, namely fornication. Under the first head there are three points of inquiry:
(1) Whether either party after the marriage has been consummated can enter religion without the other's consent?
(2) Whether they can enter religion before the consummation of the marriage?
(3) Whether the wife can take another husband if her former husband has entered religion before the consummation of the marriage?
Objection 1: It would seem that even after the marriage has been consummated one consort can enter religion without the other's consent. For the Divine law ought to be more favorable to spiritual things than human law. Now human law has allowed this. Therefore much more should the Divine law permit it.
Objection 2: Further, the lesser good does not hinder the greater. But the married state is a lesser good than the religious state, according to 1 Cor. 7:38. Therefore marriage ought not to hinder a man from being able to enter religion.
Objection 3: Further, in every form of religious life there is a kind of spiritual marriage. Now it is lawful to pass from a less strict religious order to one that is stricter. Therefore it is also allowable to pass from a less strict---namely a carnal---marriage to a stricter marriage, namely that of the religious life, even without the wife's consent.
On the contrary, Married persons are forbidden (1 Cor. 7:5) to abstain from the use of marriage even for a time without one another's consent, in order to have time for prayer.
Further, no one can lawfully do that which is prejudicial to another without the latter's consent. Now the religious vow taken by one consort is prejudicial to the other, since the one has power over the other's body. Therefore one of them cannot take a religious vow without the other's consent.
I answer that, No one can make an offering to God of what belongs to another. Wherefore since by a consummated marriage the husband's body already belongs to his wife, he cannot by a vow of continence offer it to God without her consent.
Reply to Objection 1: Human law considers marriage merely as fulfilling an office of nature: whereas the Divine law considers it as a sacrament, by reason of which it is altogether indissoluble. Hence the comparison fails.
Reply to Objection 2: It is not unreasonable that a greater good be hindered by a lesser which is contrary to it, just as good is hindered by evil.
Reply to Objection 3: In every form of religious life marriage is contracted with one person, namely Christ; to Whom, however, a person contracts more obligations in one religious order than in another. But in carnal marriage and religious marriage the contract is not with the same person: wherefore that comparison fails.
Objection 1: It would seem that even before the marriage has been consummated one consort cannot enter religion without the other's consent. For the indissolubility of marriage belongs to the sacrament of matrimony, inasmuch, namely, as it signifies the union of Christ with the Church. Now marriage is a true sacrament before its consummation, and after consent has been expressed in words of the present. Therefore it cannot be dissolved by one of them entering religion.
Objection 2: Further, by virtue of the consent expressed in words of the present, the one consort has given power over his body to the other. Therefore the one can forthwith ask for the marriage debt, and the other is bound to pay: and so the one cannot enter religion without the other's consent.
Objection 3: Further, it is said (Mat. 19:6): "What God hath joined together let no man put asunder." But the union which precedes marital intercourse was made by God. Therefore it cannot be dissolved by the will of man.
On the contrary, According to Jerome [*Prolog. in Joan.] our Lord called John from his wedding.
I answer that, Before marital intercourse there is only a spiritual bond between husband and wife, but afterwards there is a carnal bond between them. Wherefore, just as after marital intercourse marriage is dissolved by carnal death, so by entering religion the bond which exists before the consummation of the marriage is dissolved, because religious life is a kind of spiritual death, whereby a man dies to the world and lives to God.
Reply to Objection 1: Before consummation marriage signifies the union of Christ with the soul by grace, which is dissolved by a contrary spiritual disposition, namely mortal sin. But after consummation it signifies the union of Christ with the Church, as regards the assumption of human nature into the unity of person, which union is altogether indissoluble.
Reply to Objection 2: Before consummation the body of one consort is not absolutely delivered into the power of the other, but conditionally, provided neither consort meanwhile seek the fruit of a better life. But by marital intercourse the aforesaid delivery is completed, because then each of them enters into bodily possession of the power transferred to him. Wherefore also before consummation they are not bound to pay the marriage debt forthwith after contracting marriage by words of the present, but a space of two months is allowed them for three reasons. First that they may deliberate meanwhile about entering religion; secondly, to prepare what is necessary for the solemnization of the wedding. thirdly, lest the husband think little of a gift he has not longed to possess (cap. Institutum, caus. xxvi, qu. ii).
Reply to Objection 3: The marriage union, before consummation, is indeed perfect as to its primary being, but is not finally perfect as to its second act which is operation. It is like bodily possession and consequently is not altogether indissoluble.
Objection 1: It would seem that the wife may not take another husband, if her husband has entered religion before the consummation of the marriage. For that which is consistent with marriage does not dissolve the marriage tie. Now the marriage tie still remains between those who equally take religious vows. Therefore by the fact that one enters religion, the other is not freed from the marriage tie. But as long as she remains tied to one by marriage, she cannot marry another. Therefore, etc.
Objection 2: Further, after entering religion and before making his profession the husband can return to the world. If then the wife can marry again when her husband enters religion, he also can marry again when he returns to the world: which is absurd.
Objection 3: Further, by a new decree (cap. Non solum, de regular. et transeunt.) a profession, if made before the expiry of a year, is accounted void. Therefore if he return to his wife after making such a profession, she is bound to receive him. Therefore neither by her husband's entry into religion, nor by his taking a vow, does the wife receive the power to marry again.
On the contrary, No one can bind another to those things which belong to perfection. Now continence is of those things that belong to perfection. Therefore a wife is not bound to continence on account of her husband entering religion, and consequently she can marry.
I answer that, Just as bodily death of the husband dissolves the marriage tie in such a way that the wife may marry whom she will, according to the statement of the Apostle (1 Cor. 7:39); so too after the husband's spiritual death by entering religion, she can marry whom she will.
Reply to Objection 1: When both consorts take a like vow of continence, neither renounces the marriage tie, wherefore it still remains: but when only one takes the vow, then for his own part he renounces the marriage tie, wherefore the other is freed therefrom.
Reply to Objection 2: A person is not accounted dead to the world by entering religion until he makes his profession, and consequently his wife is bound to wait for him until that time.
Reply to Objection 3: We must judge of a profession thus made before the time fixed by law, as of a simple vow. Wherefore just as when the husband has taken a simple vow his wife is not bound to pay him the marriage debt, and yet has not the power to marry again, so is it in this case.