The Obligation of Zimun (Chapters 192, 193, 195, 197)
The Mishnah (Berachos 45a) states that three or more people who ate together are obligated to join together and bentch as a group, called a zimun (literally, “preparation,” or “introduction”) because they recite a collective berachah recited in the plural form, stating nevarech, “let us bentch together.”252 When a group of ten or more people eat together, Hashem’s Name – Elokeinu – is included in the zimun formula.
As a general rule, one who ate together with others and is thus obligated in zimun may not bentch on his own, without participating in zimun. Likewise, a group of ten people who ate together and are obligated to recite zimun with Hashem’s Name may not divide into smaller groups and lose their opportunity to say Hashem’s Name.253
It is a mitzvah for two people eating together to invite a third person who is present to share in their meal to create an obligation of zimun.254 Similarly, seven (or more) people sharing a meal should invite another few people to create a group of ten, so they will be obligated to say Hashem’s Name.255
The manner that zimun was instituted by the Gemara is that the leader of the zimun recites Birkas Hamazon on behalf of the other people, who would listen quietly and, in this way, discharge their obligation, instead of bentching on their own.256 In this way the zimun group would truly bentch together. It has, however, become difficult for people to focus on hearing every word said by the leader throughout the entire bentching. Since one discharging their obligation by hearing another person’s recitation must listen to every word in order to fulfill their mitzvah,257 the practice nowadays is that each person bentches on their own. The obligation of zimun is therefore instead fulfilled in one of the following ways:
Each person bentches quietly along with the leader, following him word for word.258 The other people in the group should complete each berachah slightly before the leader, so they will be able to answer Amen to his berachah.259
If it is difficult to bentch along with the leader for the entire Birkas Hamazon, one should at least recite the first berachah together with the leader reciting it out loud.260 Here, too, the other participants should finish the berachah slightly before the leader to allow them to answer Amen to the leader’s berachah.261
One who understands lashon hakodesh should ideally listen to the leader recite the first berachah of Birkas Hamazon and in this way discharge his obligation together with him. As mentioned earlier, the ideal way to perform zimun is by having the leader of the zimun recite Birkas Hamazon aloud on behalf of the other diners, who fulfill their obligation by listening to the leader’s recital instead of benching on their own. The Poskim say that if the leader knows that the diners will pay attention to his words and understand lashon hakodesh, he should inform them at the outset that they should intend to fulfill their obligation by listening to his recital of the first berachah, and he too must intend to discharge them of their obligation. The diners should be silent until the words הַזׇן אֶת הַכֹּל, listening to the leader. From there on, they themselves should recite the berachos quietly along with the leader.262
The importance of hearing the leader recite the first berachah takes precedence over saying the zimun with Hashem’s Name (Elokeinu). Therefore, if a large group of people ate together and are obligated to recite the zimun with Hashem’s Name, but, due to the large size of the room they will not hear the leader recite the first berachah, it is preferable for people sitting further away to break into smaller groups of three263 and forgo saying Hashem’s Name, rather than be part of the larger zimun and not hear the leader recite the first berachah.264
At a meal where many people are present it is best that one with a loud voice be chosen to lead the zimun to ensure that everyone present will hear him.265 Some Poskim rule that a microphone may not be used for zimun just as it is an issue in other areas of halachah (for example Megillah, and havdalah), because the sound heard by the listener is not the voice of the person speaking rather an electrical signal which produces a sound similar to the original.266 Other Poskim maintain that with zimun, hearing the leader’s actual voice is, strictly speaking, unnecessary, for zimun is not a mitzvah in which one must hear a particular sound, or text recited, rather, it is only an announcement informing the others that we will now sanctify the name of Hashem together, as a group. It is thus not necessary to directly hear the voice of the leader.267
252 Rashi ibid., ד"ה שלשה; Mishnah Berurah 192:1.
253 Shulchan Aruch 193:1.
254 Shulchan Aruch ibid.
255 Shulchan Aruch ibid. with Mishnah Berurah, note 12.
256 Beiur HaGra 195:3, ד"ה ובשאר; Meromei Sadeh, Berachos 45a; Mishnah Berurah 183, notes 27-28.
258 Shulchan Aruch 183:7.
259 Rema ibid.
260 This allows one to fulfill Rema’s position (200:2) that the obligation of zimun includes the first berachah of Birkas Hamazon. (Accordingly, one who follows Shulchan Aruch, who maintains that zimun does not encompass the first berachah of Birkas Hamazon, only needs to listen to the actual Birkas Hazimun and not the berachah of Hazan.) Nonetheless, many people are not stringent about doing so; see Shevet Halevi X:40 for a justification of their practice.
262 Mishnah Berurah ibid.
263 If people can split into smaller groups of ten without insulting the host, this is ideal.
264 Mishnah Berurah 193:17, based on Rema 200:2. Cf. Shulchan Aruch 193:1, who maintains that a group should only split up if they are unable to hear the actual Birkas Hazimun.
266 See Practical Halachah Discussions to Hilchos Shofar, Listening to Tekias Shofar through Hearing Aids, Vol. 6c, p. 829; and Practical Halachah Discussions to Hilchos Megillah, Listening to the Megillah via Artificial Means, Vol. 6f, p. 616, for discussion of this halachic topic.
267 This point is discussed in Shevet Halevi X:40, and Vezos Haberachah 14, p. 129.