# Lehre und Wehre_St. Louis Missouri_Februar 1856_S53
# AI translation — CHI Digital Archive (demonstration)

Excerpts as Contributions to Pastoral Casuistry. 53

of marriage teaches it, which is no arbitrary positive law added to marriage, but a part of the constitution of human nature itself. This nature itself is, to be sure, contingent and not necessary, but so ordered by the Creator's will; yet this ordering has been reckoned by him as belonging to the nature that man has and ought to have, and it belongs to it, only that this matter, by its very nature, like all God's free counsels, must be made known through his revelation. For God spoke, when he gave and assigned to the first man his wife, taken from him (these are God's own words, as Christ attests, Matt. 19:4–5): "For this cause shall a man leave father and mother, and shall cleave to his wife." Consequently the mother herself cannot be the wife, in which case the son would not leave his mother in order to cleave to his wife. Just as little can the daughter be the father's wife, since she is to leave him in order to cleave to her husband. "And they two shall be one flesh," Gen. 2:24; consequently, too, marriage cannot take place with the spouses of one's parents (such as with a stepmother, etc.), because through marriage they become father or mother — for the children already present from another marriage — precisely because they, together with the father or mother, are on account of the marriage to be regarded as one flesh.

The other kind of forbidden marriages occurs in the collateral line of kinship, whether of consanguinity or of affinity. It arises from two moral causes, and beyond the reach of these causes such marriages are not, unless a positive law exists, to be reckoned forbidden. The one cause is the securing of chastity in the intimate association which the nearest relatives have, and must have, with one another, since they are bound most closely to one another in the rendering of every service of friendship. The other moral cause, which tells against the marriages of overly close relatives, consists in this: that it is conducive to the common good of human society that foreign families be bound to one another through marriage. For the common welfare rests upon the social bond among men, and the intermarriage of families is one of the most important means to this, because those who marry are then regarded in the foreign family as children and siblings, and, on account of the indissolubility of marriage, share for life in benefit and harm with those to whom they are bound.

These moral causes, why the nearest relatives ought not to marry one another even in the collateral line, apply first and most strongly to siblings. For since these are ordinarily raised in one family, much evil would come about under the pretext or hope of a future marriage. But they must also, throughout life, be able to associate with one another in the closest intimacy without suspicion. For the avoidance of unchastity among them it is therefore a very sure means that between brother and sister absolutely no marriages be tolerated, and that, on the other hand, carnal