Dear Matzav.com Editor,
I would like to share an important, but often overlooked halacha. The Mishnah Berurah in Hilchos KriasShema (236:1) paskens that when davening Maariv, once the chazzan says Borchu, one should not talk, even if one did not begin the first bracha, if one is davening with that minyan. Many people are not aware of this. As a matter of fact, the Mishnah Berurah himself writes that, ba’avonoseinu harabim, many people are nichshal in this.
The Mishnah Berurah bases his p’sak on Acharonim, including the Elyah Rabbah and Pri Megadim, who say that after Borchu is considered k’emtza haperek, and once the minyan answers borchu, it is as if they started the bracha.
A Matzav Reader