Rav Yakov Emden (henceforth: RYE), who lived in Altona in the 18th century, was not only a genius of unfathomable breadth and depth but an extremely independent and courageous thinker (actually, the word “cantankerous” comes to mind and it didn't hurt that he held no official position and owned his own printing press). His book arguing against Rabbi Shimon bar Yochai’s authorship of the Zohar, Mitpachat Soferim, includes – in the words of Prof. Yeshayahu Tishby – every major argument subsequently raised by generations of scholars. His diaries, collected in Megillas Sefer, are astonishingly candid; if you think The Making of a Gadol should be banned, you’d burn his diaries with your sheitel. His teshuvos exhibit little timidity. One of his less timid teshuvos, which essentially permits sex by an unmarried couple who are living together, is the one I want to discuss. All the usual disclaimers apply.
 
The issue at hand is that of pilagshim, generally translated as “concubines”. Many biblical characters are said to have taken pilagshim: Avraham, Calev, Gideon, Dovid Hamelekh, Shlomo Hamelekh, etc. The gemara (Sanhedrin 21a) asserts that the difference between a wife and a pilegesh is that a pilegesh is “without kiddushin and without kesubah”. This is the canonical definition, accepted by almost all Rishonim. Nevertheless, the views cited in the Yerushalmi (Yevamos 5:2) can be understood as indicating that a pilegesh does get kiddushin. Moreover, the Ramban understands Rashi (Breishis 25:6) as accepting the view that a pilegesh gets kiddushin (although the Ramban himself rejects this view). The Vilna Gaon in Biur HaGra on Even HaEzer 26:1 (note 7) also argues for this view. Still, the dominant view is that the relationship between a man and a pilegesh is not marriage but rather, in RYE’s somewhat indelicate phrase “she is exclusively with him for a fixed period and specified reward as agreed between them”. (It should be added that, contrary to the popular view, a pilegesh is not a “second” wife. A pilegesh is neither a wife nor need she be secondary – the man might be otherwise unattached.)
 
So may a man and a woman live together in holy pilagshus? This is a hotly debated question among Rishonim, as we shall see, but, to get right to the point, RYE is strongly in favor. But let’s not get ahead of ourselves. The story begins pessimistically. The Rambam (Hil. Melachim 4:4) holds that only a king is permitted to take a pilegesh. This is consistent with his view that a man who has sex with a woman outside of marriage transgresses both a positive commandment (Hil. Ishus 1:1; Sefer Hamitzvos, Aseh 192) and a negative commandment (Hil. Ishus 1:4; Sefer Hamitzvos, Lo Taaseh 355). “One who has sex with a woman for the purpose of zenut without kiddushin is given lashes by Torah law, for he has had sex with a kedeshah.” (The words zenut and kedeshah are technical terms, as we will see, and are best left untranslated.)
 
The Ramban (Teshuvos HaRashba Hameyuchasos LaRamban 284) responding to a query by Rabbeinu Yonah regarding pilegesh, begins with “I don’t know what doubt there is, it is certainly permitted”. He puts forward four main points:

1. There are no grounds for forbidding it. The issur of kedeshah refers to a woman who makes her body freely available. A woman who has sex exclusively with one man is not a kedeshah. Ramban argues that this is also the Rambam’s intention when he writes “for the purpose of zenut”. (However, in Sefer Hamitzvos, Lo Taaseh 355, it’s quite clear that the Rambam forbids all sex outside marriage. Moreover, in his hasagos there the Ramban disagrees with the Rambam but on slightly different grounds: there he limits the meaning of zenut and kedeshah to cases where kiddushin is not possible, such as to a slave.) This same point is made by the Raavad in his hasagos on Hil. Ishus 1:3.

2. There are no grounds for distinguishing between a king and anybody else. In fact, it seems that although Ramban is aware (probably from Rabbeinu Yonah who so holds) that there are those who make such a distinction, his text of the Rambam does not make any such distinction. In any case, he rejects the proposed distinction as arbitrary.

3. Many biblical characters who were not kings took pilagshim and there is no indication that they were guilty of any wrongdoing.

4. Various statements in the gemara indicating that flaws in the marriage process (no brachah, diminished kesubah, unfulfilled conditions) render subsequent sexual encounters as zenut, should not be taken to mean that all sex outside proper marriage is zenut. Rather, they mean that if one takes the path of marriage, accepting the benefits and responsibilities thereof, then all the procedures must be carried out properly. However, if the path of pilagshus is taken, none of this applies.
 
Having said all that, the Ramban concludes his letter to Rabbeinu Yonah with the words “in your place, warn them away from pilagshim, for if they’ll know this heter, they will be licentious and will have sex with them in a state of nidut”.
 
Either the Ramban failed to convince both Rabbeinu Yonah and the Rashba or else they took his advice at the end of the letter to heart. Both of them (Shaarei Teshuva 3:94-95; Teshuvos HaRashba 4:314) argue that sex outside marriage (including pilegesh) is forbidden on grounds of kedeshah (even though the Rashba then goes on to argue that a pilegesh isn’t a kedeshah). The Ran (Teshuvos HaRan 68), however, agrees with the Ramban that pilegesh is permitted.  

Another view worth mentioning is that the negative commandment mentioned by the Rambam does indeed apply only to a true kedeshah and not to a pilegesh but the positive commandment to take a woman through the procedure of marriage is violated by pilagshus. The Rivash (Teshuvos HaRivash 395) attributes this view to the Raavad; the Gaon (Biur HaGra on Even HaEzer 26:1, note 8) attributes it to the Rambam.

RYE picks up the ball from the Ramban. To be continued…