By Rabbi Berach Steinfeld
The Taz in Orach Chaim 494 writes that we delay davening Maariv on Shavu
The Teshuvos Lehoros Nosan Vol 7:31writes that women, despite the fact that they are exempt from Sefiras HaOmer, are still required to wait and not make Kiddush until after tzais hakochavim. The reason for this is that the Yom Tov of Shavuos is different than any other Yom Tov in that the time of the month is not explicitly written in the Torah, whereas regarding all other Yomim Tovim, the Torah specifies a date. Shavuos is identified as being seven weeks after the second day of Pesach. Since the Torah identified this Yom Tov as being seven weeks after Pesach, it must be complete weeks and therefore even women would be required to wait for Kiddush so as to bring in the Yom Tov on time. This would seem to be a big nafka mina for the women. Normally, on the first day of Yom Tov, women light while it is still day and are mekabel Yom Tov early, hereby enabling them to make the bracha of shehechyanu. On the night of Shavuos it would behoove the women to light later on so the bracha of shehechyanu is said at the right time.
Another question that can be analyzed is; what would be if somebody forgot to make the bracha of shehecheyanu on
We could answer that since during this time one would have a mitzvah of visiting his Rebbe, the simcha of greeting his Rebbe would warrant one to make the bracha of shehecheyanu. What would result based on this tirutz is that if someone forgot to say shecheyanu on Shavuos, he would have to go visit his Rebbe and thereby make-up the bracha of shecheyanu.
May we be zocheh to be mekayem the mitzvah of greeting our Rebbe in person in our schools and Batai Medrash together with Moshiach Tzidkeinu and say the bracha of shehecheyanu
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