1) It is extremely important to refrain from talking “Sichas Chulin– mundane conversation” in a Shul, especially during davening and surely during Chazaras HaShatz and Krias HaTorah.
One who talks during Chazaras HaShatz is a sinner, and this sin is too great for any individual to bear (This is the one and only place the Shulchan Aruch uses such language regarding not keeping a Halacha. The reason for this is that just as when Kayin killed Hevel he virtually killed half of the world and Hashem told him that his sin is too great to bear, so too one who talks during davening is not only harming himself, but he/she is harming their children and all the other people in the Tzibbur, as when there is talking in Shul it causes the Shechinah to leave, and causes the tefilos of the entire shul to not be “heard and” accepted by Hashem. Based on Tosefos Yom Tov, Sefer HaGan Derech Moshe, Igeres HaKodesh of MaHarDaB of Lubavitch and other commentaries)
2) All Jews are instructed to [respectfully] chastise anyone who talks during Chazaras HaShatz. It should first be done in a way that the offender isn’t being singled out, rather a s a general “announcement” to the Shul that it is too noisy. If that doesn’t work, the individual should be approached quietly.
If one is told to be quiet and he ridicules the person rebuking him/her, they are subject to the [ quite unpleasant] rules prescribed in the Rambam (Hilchos De’os Perek 6:7) and may eventually be barred from entering the Shul.
If one will talk in Shul, it is better for him/her to not come in the first place (Kaf HaChaim Siman 151:8 and Chida in Sefer Pesach Einayim)
This is not a Minhag (custom), Chumra (stringency) or Midas Chasidus (something only pious people do). It is an undisputed Halacha Mefureshes in Shulchan Aruch Siman 124:7 with its source in the words of Chazal and the Rishonim.
3) Many sharp words have been written about the gravity and dire consequences of transgressing the sin of talking during davening, yet unfortunately too many otherwise religious Jews are still very lax when it comes to talking in Shul. I will quote below just a small sampling of the plethora of sources bemoaning this sinful practice, in the hopes that it may help people to start taking this Halacha more seriously and thus hasten the coming of Mashiach:
* One who talks while the Tzibbur is praising Hashem Yisborach (i.e. during Chazaras HaShatz) is showing that he wants no part in [the praising of] Hashem (Shulchan Aruch HaRav Siman 124:10 quoting the Zohar in Parshas Terumah)
* Woe is to those that talk during Chazaras HaShatz, as many Shuls throughout Jewish history have been destroyed due to this sin. (Mishna Berura 124:27 quoting the Elya Rabbah).
* Many Shuls have been turned into churches due to the fact that talking took place in those Shuls. (Mogen Avraham Siman 151)
* One who talks during davening, his mouth becomes “Tamei- impure”, and when he davens with this mouth it is as if he is being Oved Avoda Zara- serving idols (Drashos Chasam Sofer Vol. 2 Drasha for 7 Av)
* One who talks during davening has no portion in Olam Haba, the world to come. (Sefer M’Am Loez Parshas Bamidbar)
* The holy Rebbe of Gur, the Imrei Emes Zatzal, was known to have said that the tragedy of the holocaust that befell the Jewish people and cost us 6,000,000 lives, was brought upon us due to the sin of talking during davening, and the reason the Sephardic communities were for the most part spared, was due to their being scrupulous in not talking during davening (Quoted in Sefer Tuvecha Yabiu Vol. 2 Page 321)
* Talking during Tefilah is delaying the Geulah (final redemption/coming of Mashiach)
(Sefer Yesh Nochlin from the father of the Shl”a HaKadosh. See also Sefer Mikdash Me’at Page 27 and Shu”y Yabia Omer from Rav Ovadia Yosef Shlita Vol. 1 Siman 10:11)
* Talking during davening is the worst Aveira a Jew can do! It causes the Yetzer Hara to become empowered over the person, and one who talks during davening is a Choteh U’Machtee Es HaRabim- causes others to follow in his ways and sin as well, and is degrading the glory of Hashem (Sefer Yesh Nochlin ibid.)
4) Every Shul should appoint a G-d fearing, strong person to be a Mashgiach to reprimand and punish those who talk during davening (Vavei HaAmudim quoted in Pri Megadim Siman 124:11, and in Mishna Berura 124:27).
The congregation should support and assist the aforementioned “Mashgiach”, and by doing so they will merit to have their Tefilos answered. (Sefer Birchas HaBayis Sha’ar 42)
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