As noted on yesterday’s daf , one suggestion that appears in the Gemara to explain the disagreement between the Tanna Kamma (first) and Rabban Gamliel is that the Tanna Kamma believes that there is an obligation to wear tefillin on Shabbat. On our daf the Gemara discusses why such an obligation does or does not exist.
The basic source to limit the commandment of tefillin to weekdays is quoted in the name of Rabbi Akiva, who understands the passage about tefillin “…and they shall be a sign (ot) on your hand and a remembrance between your eyes…” (Shmot 13:9) to mean that tefillin are only necessary when there is a need for an ot – a sign. On days that are considered, in and of themselves an ot, there is no need to don tefillin. There are many different explanations as to what makes Shabbat and Yom Tov (Jewish holiday) days that are considered an ot. Some explain that the commandments regarding the holiness of these days make them a sign for the Jewish people. Some say that it is the fact that work is forbidden that makes such days stand out on the calendar as a sign. Yet others argue that it is the unique commandments of each of the days – sukka, matza, refraining from eating hametz, etc.
In the course of the discussion, the Gemara relates a well-known midrash:
Michal, daughter of Kushi, King Saul, would don phylacteries, and the Sages did not protest against her behavior, as she was permitted to do so. And similarly, Jonah’s wife would undertake the Festival pilgrimage and the Sages did not protest against her practice. From the fact that the Sages did not protest against Michal’s donning phylacteries, it is apparent that these Sages hold that phylacteries is a positive mitzva not bound by time, i.e., it is a mitzva whose performance is mandated at all times, including nights and., There is an accepted principle that women are obligated in all positive mitzvot not bound by time.
This argument is rejected by the Gemara, since Michal may have been wearing tefillin not because she saw it as an obligation, but because she chose to do so voluntarily, following the opinion of Rabbi Yose who rules that women can participate in mitzvot voluntarily, even if they are not obligated in them. Specifically, Rabbi Yose permitted women to do semikha – to lean on a sacrifice that they are bringing to the Temple – even though they are not obligated to do so.
Our tradition follows the opinion of Rabbi Yose which allows women to perform mitzvot on a voluntary basis, even if they are not commanded in them. Rabbi Yose permits this even in a case where there is potential for a transgression, as in the case of semikha, which can be seen as making use of an animal that has been consecrated as a sacrifice, which is ordinarily forbidden.
The story about Michal bat Kushi does not appear in Tanakh, but it was a well-established tradition handed down to the sages. It is interesting to note that when the story is recorded in the Jerusalem Talmud, it tells that the sages did object to her participation in this mitzva, which is why women are discouraged from participating in the mitzva of tefillin, as opposed to other mitzvot (shofar, lulav, etc.), which women are encouraged to fulfill.