1 We lately put forth a book “of the Good of Marriage,” in which also we admonished and admonish the virgins of Christ, not, on account of that greater gift which they have received, to despise, in comparison of themselves, the fathers and mothers of the People of God; and not to think those men, (whom the Apostle sets forth as the olive, that the engrafted wild olive be not proud,) who did service to Christ about to come hereafter, even by the begetting of sons, on this account of less desert, because by divine right continence is preferred to wedded life, and pious virginity to marriage.
Forsooth in them were being prepared and brought forth future things, which now we see fulfilled in a marvellous and effectual manner, whose married life also was prophetic: whence, not after the wonted custom of human wishes and joys, but by the very deep counsel of God, in certain of them fruitfulness obtained to be honored, in certain also barrenness to be made fruitful. But at this time, towards them unto whom it is said, “if they contain not, let them be married,” we must use not consolation, but exhortation. But them, unto whom it is said, “Whoso can receive, let him receive,” we must exhort, that they be not alarmed; and alarm that they be not lifted up. Wherefore virginity is not only to be set forth, that it may be loved, but also to be admonished, that it be not puffed up.
Source: On Holy Virginity (New Advent)