St. Ambrose answers objections made to the uselessness of his exhortations in favour of virginity, and brings forward instances of virgins especially in various places he mentions, and speaks of their zeal in the cause.
57. Some one may say, you are always singing the praises of virgins. What shall I do who am always singing them and have no success? But this is not my fault. Then, too, virgins come from Placentia to be consecrated, or from Bononia, and Mauritania, in order to receive the veil here. You see a striking thing here. I treat the matter here, and persuade those who are elsewhere. If this be so, let me treat the subject elsewhere, that I may persuade you.
58. What is it, then, that even they who hear me not follow my teaching, and those who hear me follow me not? For I have known many virgins who had the desire, but were prevented from going forward by their mothers, and, which is more serious, mothers who were widows, to whom I will now address myself. For if your daughters desired to love a man, they could, by law, choose whom they would. Are they, then, who are allowed to choose a man not allowed to choose God?
59. Behold how sweet is the fruit of modesty, which has sprung up even in the affections of barbarians. Virgins coming from the most distant on this and that side of Mauritania desire to be consecrated here; and though all the families be in bonds, yet modesty cannot be bound. She who mourns over the hardship of slavery avows an eternal kingdom.
60. And what shall I say of the virgins of Bononia, a fertile band of chastity, who, forsaking worldly delights, inhabit the sanctuary of virginity? Not being of the sex which lives in common, attaining in their common chastity to the number of twenty, and fruit to an hundredfold, leaving their parents' dwelling they press into the houses of Christ, as soldiers of unwearied chastity; at one time singing spiritual songs, they provide their sustenance by labour, and seek with their hands supplies for their liberality.
61. But if the attraction of searching for virgins has grown strong (for they beyond others follow up the search and watch for purity), they follow up their hidden prey with the greatest perseverance to its very chambers; or, if the flight of any one shall have seemed more free, one may see them rise on the wing, hear the rustling of their feathers, and the bursting of applause; so as to surround the one on wing with a chaste band of modesty, until rejoicing in that fair companionship, forgetful of her father's house, she enters the regions of modesty and the fenced-in home of chastity.
Source: Concerning Virgins (New Advent)