The Mishna on today’s daf discusses one of the laws of a Jewish king – that he cannot marry many wives (see 17:16), lest they lead him astray. Based on this passage, the Mishna limits a king to having 18 wives. Rabbi Yehuda suggests that if they do not lead him astray then it would be permissible to marry many wives. Rabbi Shimon disagrees, pointing out that even a single wife who leads him astray would be forbidden, thus the Torah must mean that even many righteous wives, like King David’s wife Avigail, would be forbidden.
In the continuation of the Gemara we are taught that although King David appears to have married many wives – see II Shmuel 5:13 – nevertheless the number did not exceed 18. In explanation of the pasuk‘s reference to nashim (wives) and pilagshim (concubines), Rav Yehuda quotes Rav as explaining that nashim are properly married with ketuba and kiddushin, while pilagshim have neither ketuba nor kiddushin. Furthermore, Rav Yehuda quotes Rav as teaching that there were 400 soldiers in King David’s army who were the offspring of his relations with an eshet yefat to’ar (see 21:10) who behaved like non-Jews, cutting their hair, for example, in the fashion of non-Jews, and growing a blorit.
Many suggestions are offered to define the term blorit, but no word in Greek or Latin is a perfect match for it. The hairstyle involved allowed the hair to grow long particularly on the sides and in the back of the head, and the hair was tied and braided into different shapes. Later on, the braided hair was shaved off in a special pagan ritual ceremony.
While it is difficult to imagine that King David could have limited himself to 18 wives yet fathered 400 children from his relations with neshot yefat to’ar, Rashi in Massekhet Kiddushin (76b) suggests that the children referred to in this story were not King David’s own. Rashi suggests that King David took responsibility for the children fathered by his soldiers under those circumstances so they were raised in his home.