What is the status of a Pilegesh?
Sanhedrin 21a: A wife has Kesuvah and Kidushin. A Pilegesh (concubine) does not have Kesuvah, and not Kidushin.
Ra'avad (Hilchos Ishus 1:4): Some texts in Sanhedrin 21a say that a Pilegesh has Kidushin, but not Kesuvah. Yam Shel Shlomo (Yevamos 2:11) - Rashi (Bereishis 25:6) had such a text; he says that a wife has a Kesuvah, but a Pilegesh does not. 1 The Yerushalmi (Kesuvos 5:2) implies like this. Tana'im argue about whether or not she has a Kesuvah. This implies that all agree that she has Kidushin 2 . Kesuvah is lest it be light in his eyes to divorce her! Yalkut Shimoni (Shmuel 2, 151) says that Achitofel planned to execute Avshalom for raping his father's Pilagshim. They must have Kidushin! Bereishis Rabah 32:1 calls it Giluy Arayos. Ba'al Pilegesh b'Giv'ah is called her husband, and her father is called his father-in-law (19:3-5).
Ramban (Bereishis 25:6) - Kesuvah is mid'Rabanan. The Torah cannot distinguish wives from Pilagehim based on Kesuvah alone 2
! Gur Aryeh (25:6): A woman can pardon the Kesuvah. If she did so, is she called a Pilegesh due to this?! (Why is this difficult? R. Meir holds that if the Kesuvah is less than Chachamim mandated, their Bi'ah is Zenus (Kesuvos 5:1)! Meleches Shlomo (5:1) ? if she has no Kesuvah, all call this Bi'as Zenus! ? PF)
Is it permitted to have a Pilegesh?
Rambam (Hilchos Melachim 4:4): It is permitted only for a king, or an Amah Ivriyah after Yi'ud.
Rashba (Teshuvah 284, attributed to Ramban): A Pilegesh is designated for one man. There is no source in Torah to forbid, and we do not find that Chachamim decreed to forbid. The Gemara does not distinguish a king from a commoner. Gedolei Yisrael had Pilagshim, e.g. Kalev, (Divrei ha'Yamim 1 2:46) and Gid'on (here). 1 If it were forbidden, Ba'al Pilegesh b'Giv'ah would have been ashamed of his sin! 2
Rashba: If you will say that a Shofet is like a king, and his Pilegesh is known (so it is permitted), there is no clear distinction (for whom it is permitted).
