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.
Concubinage in general was struck at by the concordat between the Pope Leo X.
The bishop of Utrecht supported him warmly, and got him to preach against concubinage in the presence of the clergy assembled in synod.