Chapter 5 [IV.]—The Natural Good of Marriage. All Society Naturally Repudiates a Fraudulent Companion. What is True Conjugal Purity? No True Virginity and Chastity Except in Devotion to True Faith.

The union, then, of male and female for the purpose of procreation is the natural good of marriage. But he makes a bad use of this good who uses it bestially, so that his intention is on the gratification of lust, instead of the desire of offspring. Nevertheless, in sundry animals unendowed with reason, as, for instance, in most birds, there is both preserved a certain kind of confederation of pairs, and a social combination of skill in nest-building; and their mutual division of the periods for cherishing their eggs and their alternation in the labor of feeding their young, give them the appearance of so acting, when they mate, as to be intent rather on securing the continuance of their kind than on gratifying lust. Of these two, the one is the likeness of man in a brute; the other, the likeness of the brute in man. With respect, however, to what I ascribed to the nature of marriage, that the male and the female are united together as associates for procreation, and consequently do not defraud each other (forasmuch as every associated state has a natural abhorrence of a fraudulent companion), although even men without faith possess this palpable blessing of nature, yet, since they use it not in faith, they only turn it to evil and sin. In like manner, therefore, the marriage of believers converts to the use of righteousness that carnal concupiscence by which “the flesh lusteth against the Spirit.”^20692069     Gal. v. 17. For they entertain the firm purpose of generating offspring to be regenerated—that the children who are born of them as “children of the world” may be born again and become “sons of God.” Wherefore all parents who do not beget children with this intention, this will, this purpose, of transferring them from being members of the first man into being members of Christ, but boast as unbelieving parents over unbelieving children,—however circumspect they be in their cohabitation, studiously limiting it to the begetting of children,—really have no conjugal chastity in themselves. For inasmuch as chastity is a virtue, hating unchastity as its contrary vice, and as all the virtues (even those whose operation is by means of the body) have their seat in the soul, how can the body be in any true sense said to be chaste, when the soul itself is committing fornication against the true God? Now such fornication the holy psalmist censures when he says: “For, lo, they that are far from Thee shall perish: Thou hast destroyed all them that go a whoring from Thee.”^20702070     Ps. lxxiii. 27. There is, then, no true chastity, whether conjugal, or vidual, or virginal, except that which devotes itself to true faith. For though consecrated virginity is rightly preferred to marriage, yet what Christian in his sober mind would not prefer catholic Christian women who have been even more than once married, to not only vestals, but also to heretical virgins? So great is the avail of faith, of which the apostle says, “Whatsoever is not of faith is sin;” ^20712071     Rom. xiv. 23. and of which it is written in the Epistle to the Hebrews, “Without faith it is impossible to please God.”^20722072     Heb. xi. 6.