Question
What is the origin of the requirement that married women must cover their hair?
Answer
Married women have covered their hair since Biblical times. In Num.5:18, when a woman suspected of adultery comes to the Temple to drink the “bitter waters”, the priest uncovers her hair; this implies that ordinarily it was covered. The Mishnah (Kesubos 7:3) calls covering the hair a “Jewish ordinance” (das Yehudis). See also Gemara, 72a; and Shulchan Aruch Orach Chayim 75:2 and Even Ha-Ezer 21:2.