18 Another charge brought against me is simply intolerable! It is urged that in explaining the apostle's words concerning husbands and wives, “Such shall have trouble in the flesh,” I have said: “We in our ignorance had supposed that in the flesh at least wedlock would have rejoicing. But if married persons are to have trouble in the flesh, the only thing in which they seemed likely to have pleasure, what motive will be left to make women marry? For, besides having trouble in spirit and soul, they will also have it even in the flesh.” Do I condemn marriage if I enumerate its troubles, such as the crying of infants, the death of children, the chance of abortion, domestic losses, and so forth? Whilst Damasus of holy memory was still living, I wrote a book against Helvidius “On the Perpetual Virginity of the Blessed Mary,” in which, duly to extol the bliss of virginity, I was forced to say much of the troubles of marriage. Did that excellent man— versed in Scripture as he was, and a virgin doctor of the virgin Church— find anything to censure in my discourse? Moreover, in the treatise which I addressed to Eustochium I used much harsher language regarding marriage, and yet no one was offended at it. Nay, every lover of chastity strained his ears to catch my eulogy of continence. Read Tertullian, read Cyprian, read Ambrose, and either accuse me with them or acquit me with them. My critics resemble the characters of Plautus. Their only wit lies in detraction; and they try to make themselves out men of learning by assailing all parties in turn. Thus they bestow their censure impartially upon myself and upon my opponent, and maintain that we are both beaten, although one or other of us must have succeeded.
Moreover, when in discussing digamy and trigamy I have said, “It is better for a woman to know one man, even though he be a second husband or a third, than several; it is more tolerable for her to prostitute herself to one man than to many,” have I not immediately subjoined my reason for so saying? “The Samaritan woman in the Gospel, when she declares that her present husband is her sixth, is rebuked by the Lord on the ground that he is not her husband.” For my own part, I now once more freely proclaim that digamy is not condemned in the Church— no, nor yet trigamy— and that a woman may marry a fifth husband, or a sixth, or a greater number still just as lawfully as she may marry a second; but that, while such marriages are not condemned, neither are they commended. They are meant as alleviations of an unhappy lot, and in no way redound to the glory of continence. I have spoken to the same effect elsewhere. “When a woman marries more than once— whether she does so twice or three times matters little— she ceases to be a monogamist. 'All things are lawful...but all things are not expedient.' I do not condemn digamists or trigamists, or even, to put an impossible case, octogamists. Let a woman have an eighth husband if she must; only let her cease to prostitute herself.”
Source: Letters (New Advent)