The Shofar is sounded near the end of Yom Kippur. As we’ve written, there is a link between Rosh Hashanah and Yom Kippur. (The Rabbis actually derived the Shofar of Rosh Hashanah from the mention of Shofar on Yom Kippur of the Yoveil — fiftieth year.)
Issues
There are numerous questions regarding this practice.
First question: What’s the purpose of Shofar at Yom Kippur every year? The Torah discusses Shofar at Yom Kippur of the fiftieth year only!
At one point (Shabbos 114b), Tosafos says that every year gets a ‘zecher’ to the Yoveil (the fiftieth year). The Shofar of Yom Kippur reminds us of Yoveil.
Second question: How is it permissible to sound the Shofar on Yom Kippur?
The day is not completely over; even if it were over, some kind of Havdala has to be said before doing Melacha. (The Chazan doesn’t say “hamavdil bein kodesh l’chol”.)
Shofar is not actually a forbidden act of labor. The Rabbis forbid sounding the Shofar on Shabbos because it is a skill which requires knowledge. They were concerned that the blower would have some doubt and carry the Shofar in a place where it is forbidden to carry.
However, the Shofar of Yom Kippur in our days, since it’s merely to remind us of something (i. e. Yoveil), does not have the extensive laws of the Rosh Hashanah Shofar. We are not concerned that the blower will have doubts and carry the Shofar in a forbidden place.
Elsewhere (Megillah 4b), Tosafos questions whether the purpose of Shofar at the end of Yom Kippur is to remind us of Yoveil (for in that case it would only be needed once in fifty years).
The “Taz” (O. C. 623) writes that is in order to remind us of the departure of the Shechina after the Giving of the Torah. (The final day of the giving of the Tablets was on Yom Kippur, after Hashem was reconciled with Klal Yisrael.)
Others say that the Shofar at the end of Yom Kippur is to give notice that the day is ending and it’s time for the women to head home to feed the children.
At any rate, this Shofar sounding does not derive from a Torah command and Tosafos’ logic (1) might be valid.
However, Tosafos had written that only one sound of ‘tekia’ is sounded after Yom Kippur, and that’s why it’s not such a skill. Others have the custom of sounding a full set of ‘tekia shevarim teruah tekia’ in which case it may well be considered a skill.
However, there are other answers as to how we can sound the Shofar at the end of Yom Kippur. The Rashbam writes that this late in the day is considered Tosefes Yom Kippur (2); the decree of the Rabbis not to sound the Shofar on Shabbos does not apply at this point. The Mishnah Berurah cites the view that at this late time (bein hashmashos — twilight) a prohibition from the Rabbis — done for the sake of a mitzva — does not apply.
G’mar Chasima Tova!
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1.Since it’s not such a skill to blow at this point, we are not concerned that the blower will have doubts and carry the Shofar in a forbidden place.
2.Additional part of the day.