Our Lady preserved her virginity all her life. The Church Fathers wondered if Mary had made a vow to remain a virgin. St. Thomas Aquinas summarizes their thoughts on this subject.
The starting point of this reflection is Mary’s response to the Archangel Gabriel who announces her motherhood: “How will this be done since I know no man?” (Lk. 1:26). To properly understand this answer, it must be remembered that the verb “to know” is used by Sacred Scripture to speak of carnal relationships.
Since the Virgin Mary is engaged to St. Joseph – an engagement that among the Jews is almost equivalent to marriage – this question denotes the fact of virginity with the intention of preserving it in the spirit of consecration to God.
This is how St. Augustine understands it: “At the announcement made by the Angel, Mary answers: ‘How will this be done, since I know no man?’ What she would certainly not have said if she had not previously consecrated her virginity to God” De sancta virginitate (quoted by St. Thomas). Many Fathers followed St. Augustine.
The Beautiful Explanation of the Common Doctor
In the exposition of the suitability of this vow, saint Thomas puts forward the principle of attribution of privileges: it is necessary to assume the most perfect in the Blessed Virgin, but the virginity consecrated by vow is more perfect than the virginity not consecrated. So she made that vow.
The Angelic Doctor explains elsewhere that “what is done by vow is more perfect. But the main purpose of the vow is to strengthen the will in the good.” He also says that to a “will already sanctified like that of Our Lady, who enjoys perfect virtue, it is not useful to make many vows”.
He therefore asks himself the question: “Why that of virginity, when it was enough to practice perfect chastity?” The answer is very beautiful and clear: “because that he fixes in a state of life”, so that in the act of such a vow one can make the gift of his whole life.
He further specifies: “If we compare it to the other vows of religion, that of obedience is sufficiently replaced by the commitment of marriage, under the authority of Saint Joseph, and that of poverty is not prudent for a mother.”
However, he notes that the mores of the time would not have accepted that a woman does not marry, because all the members of the chosen people had to participate in its propagation. So he believes with some Fathers that the Virgin was first engaged to Joseph, and that then, by mutual agreement, they would both have taken a vow of virginity.
But it is also possible, according to other authors, that Joseph and Mary’s agreement took place before the engagement, and that they made the vow before they were married.
Cardinal Cajetan – a great commentator on St. Thomas – adds: “Is it not natural to think that this holy husband, by granting his wife to dedicate his virginity while remaining in marriage, made the same vow himself at the same time?
Having regard above all to divine providence, which had to inspire Joseph with this resolution, so to speak, that the Blessed Virgin might have as a companion and guardian a spouse who was equally virgin. Moreover, Mary would not have been ‘full of grace’ if this grace, which she was to desire above all in her fundamental rectitude, had been lacking in her husband.”
Thus the Virgin Mary is, according to the common opinion, the first to make the vow of virginity, according to time and according to the perfection of the act.