“Question: Can a lady write a Sefer Torah? And if not, why not?
Discussion: The Gemoro (Gittin 45b) clearly states that a Sefer Torah written by a lady is invalid, and explains that the reason for this is because it says in the pesukim (regarding Tefillin and Mezuzos respectively) “”u’kshartem… u’ksavtem”” “”and you shall tie them [i.e. the Tefillin onto your arm and head] and you shall write them [i.e. Mezuzos; to be placed] on the doorposts of your houses and gates””. The Gemoro (ibid) infers from the juxtaposition of “”writing”” Mezuzos to “”tying”” Tefillin that whoever tying [Tefillin] applies to, has the Halachic ability to write [Mezuzos]; and whoever is exempt from tying [Tefillin], is invalidated to write [Mezuzos].
Thus, women who are exempt from wearing Tefillin are invalidated to write Mezuzos. The reason that women are exempt from wearing Tefillin is because Tefillin is a mitvas aseh she’hazman geromo (a time dependent mitzva) since Tefillin are not worn on Shabbos and Yom Tov.
Although the “”writing”” mentioned by the posuk refers to Mezuzos, it appears clear from the context of the Gemoro that the inference is a general one and equally applies to Tefillin and Sifrei Torah and not only to Mezuzos. [Otherwise, how can the Gemoro bring as a source for the din that women are invalidated from writing Sifrei Torah the juxtaposition of “”u’kshartem… u’ksavtem” which pertains to Mezuzos; maybe Sifrei Torah are different? We are forced to say that the Gemoro extrapolates from Mezuzos to Sifrei Torah.]
The Tur (Yoreh De’ah Siman 281) in Hilchos Sefer Torah omits the aforementioned Gemoro and makes no mention of an invalidation of a Sefer Torah written by a lady. However, the Beis Yosef (Yoreh De’ah Siman 281 se’if 3) does quote the Gemoro, and also quotes several Rishonim (the Rif, the Rosh in Hilchos Tefillin, and the Ran) who rule in line with the Gemoro. The Ran clearly writes that we extrapolate from Mezuzos to Sifrei Torah “because they [i.e. Sifrei Torah] are holier” [than Mezuzos; i.e. if women are invalid to write Mezuzos, then all the more so they are invalid to write Sifrei Torah].
The Drisha (Yoreh De’ah Siman 281 s.k. 1) notes that the Tur omits this ruling, and also notes that both the Rif and the Rosh omit this ruling in their Hilchos Sefer Torah, and surmises that these authorities differentiate between Tefillin [that are invalid when written by a lady] and a Sefer Torah [that is valid when written by a lady].
The Shulchan Aruch (Yoreh De’ah Siman 281 se’if 3) clearly invalidates a Sefer Torah written by a lady. The Shach (s.k. 6) comments on this and says that although the Drisha does suggest that according to the Rif, Rosh and Tur there may be a difference between Tefillin and Sefer Torah [and therefore a Sefer Torah written by a lady may in fact be kosher], the differentiation of the Drisha is not conclusive [and the same invalidation applies to Sifrei Torah].
Conclusion: Although several Rishonim surprisingly omit the clear and undisputed ruling of the Gemoro that a Sefer Torah written by a lady is invalid, and the Drisha suggests that these authorities may in fact validate such a Sefer Torah, the clear Halachic conclusion of the Shulchan Aruch is that such a Sefer Torah is indeed invalid, and this ruling is unanimously upheld by the major Halachic authorities (namely the Remo and Taz who do not comment or argue on the ruling of the Shulchan Aruch, and it appears from this that they agree to his ruling; also the Shach who appears to conclude in disagreement with the Drisha).
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