The great medieval canon lawyer Lyndwood illustrates the difficulty of distinguishing, even as late as the middle of the 15th century, between concubinage and a clandestine, though legal, marriage.
It is good for a man not to touch a woman; a man's relations with his own wife are merely a means of fornication, and marriage and concubinage are indistinguishable as against the kingdom of God, in which there is no marrying or giving in marriage.
The Koreans are rigid monogamists, but concubinage has a recognized status.
The bishop of Utrecht supported him warmly, and got him to preach against concubinage in the presence of the clergy assembled in synod.
These conciliatory prelates were sincere supporters of the reformation, and combated simony, the marriage or concubinage of priests, and the immorality of sovereigns with the same conviction as the most ardent followers of Gregory VII.