In brief, a woman's voice (Kol Isha) is considered ervah or nakedness. Normative Jewish law enjoins a woman from singing in front of men. She is not (yet) prevented from speaking to, or before, men, and I'm not familiar with any discussion of chanting, or other in-between categories.
In any event, if singing is certainly banned how can a woman be permitted to lead a prayer service in front of men? Isn't her singing immodest?
Well, not so fast. Here are the facts not yet established:
(1) Is leading a prayer service really "singing"? Its not a performance. The leader's back is to the congregation, and she is addressing God. Any eye contact she might make is with Him. Also, I'm certain its possible to lead without singing, at least per the most ordinary definition. When I lead, I intone (that is I speak in a singing voice) Does that count?
(2) Are women really forbidden from singing in a shul? Are they required to sit silently during the congregational songs (or, in shteebles, the congregational humming)? This strikes me as needlessly exclusive. Perhaps there's an exception for shul singing?
(3) Is the ban on singing applicable today? This depends on the nature of the prohibition. Do we say that women are banned from singing because of the effect the signing might have on men, or do we say that there's something inherently immodest about a woman's voice? I'm not sure. If the ban on signing is like the ban on going topless, that's one thing, but if female singing was banned because once upon a time it made men horny, I think we can agree the prohibition has outlived its usefulness. Today, ordinary men are not affected this way by singing women (and certainly not by a women chanting Psalms with her back to us)
Expert readers, what do you know and will you share some of this knowledge with us?
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