In the preceding chapter on fornication, pellicacy also was treated of, and by pellicacy was meant a stipulated conjunction of an unmarried man with a woman. By concubinage is here meant the conjunction of a married man with a woman, likewise stipulated. Those who make no distinction between kinds, use these two words as if they had the same meaning and therefore designated the same thing; but they are two different kinds of relationship, the word pellicacy being suitable to the one--a mistress [pellex] being a harlot--and the word concubine to the other--a concubine being an additional partner [succuba] of the bed. Therefore, for the sake of separating them, an ante-nuptial stipulation with a woman is designated as pellicacy, and a post-nuptial stipulation as concubinage. Concubinage is here treated of for the sake of order, it being from order that, on the one hand, the nature of marriage is disclosed, and on the other, the nature of adultery. First it was shown that marriage and adultery are opposites, this being the subject of the chapter on that opposition. How greatly they are opposite, and the nature of their opposition, can be gathered only from the intermediate relationships which lie between them, of which concubinage is one. Because there are two kinds of concubinage, and an absolute distinction must be made between them, this chapter like the preceding shall be distributed into its parts, as follows:
I. That there are two kinds of concubinage, which greatly differ from each other; one conjointly with the wife, the other in separation from the wife.
II. That for Christians, concubinage conjointly with the wife is altogether unlawful and detestable.
III. That it is polygamy, which is banned from the Christian world, and should be banned.
IV. That it is whoredom, and by it the conjugial, which is the precious treasure of Christian life, is destroyed.
V. That concubinage in separation from the wife, when engaged in from causes legitimate, just, and truly weighty, is not unlawful.
VI. That the legitimate causes of this concubinage are legitimate causes of divorce, the wife being nevertheless retained in the home.
VII. That the just causes of this concubinage are just causes of separation from the bed.
VIII. That the weighty causes of this concubinage are real and unreal.
IX. That weighty causes are real when based on what is just.
X. But that weighty causes are unreal when not based on what is just, even though on an appearance thereof.
XI. That those who are in this concubinage from causes legitimate, just, and really weighty, may at the same time be in conjugial love.
XII. That while this concubinage continues, actual conjunction with the wife is not lawful.
The explanation of the above now follows: