…Our practice for gabbaim is mixed: There is never a gabbai on Friday nights (except on the rare occasion when someone other than one of the rabbis reads Torah, in which case one of the rabbis will serve as gabbai); there is always a gabbai (even when the Ba'al/Ba'alat K'riyah is a rabbi) in our Shabbos morning minyan; and, as mentioned above, a rabbi serves as gabbai on Shabbos morning for the Bar/Bat Mitzvah. When present, the gabbai a) calls the aliyot (and prompts the olim, if necessary), b) prompts the Ba'al/Ba'alat K'riyah, c) recites the M'Shebeirach L'Olim v'Korim, and d) may also recite any other blessings, such as the blessing for the new moon on Shabbat Mevarchim (the Shabbat before Rosh Chodesh)…
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