Definition of Tefilla B'tzibur

The combination of davening with a small minyanon campus and of people running very tight schedules often times raises the question of how many men need to start the shmoneh esreh together in order to have a tefilla b’tzibur.
At first glance it seems clear from the language of the Rambam[1]that it is enough to have as few as 6 men start shmoneh esreh together for it to be considered a tefilla b’tzibur. The Rambam rules that if there are 6 men who did not yet daven they can add 4 men who already davenedand make a minyan. Interestingly though, some of the poskim understand the Rambam’s ruling differently.

What should we do before our minyan looks like this?

Rav Avraham Danziger in his Chayey Adam[2]writes that for davening to qualify as a tefilla b’tzibur 10 men need to start shmoneh esreh at the same time. The Mishnah Berura[3]seems to follow this ruling as he quotes the Chayey Adam and does not mention another opinion. Rav Moshe Feinstein[4]explains that this ruling does not contradict the abovementioned opinion of Rambam because he is referring to the repetition of shmoneh esreh alone as opposed to the silent amidah which he agrees must be recited by 10 men simultaneously in order for it to be considered a tefilla b’tzibur.
However, we find other poskim who take a different approach. Rav Betzalel Stern[4.1] discusses all of the aforementioned sources and argues that the Chayey Adam, upon which the rulings of the Mishnah Berura and Igrot Moshe are leaning, can be interpreted differently. Rav Stern claims that the Chayey Adam only meant to say that it is not enough for 10 men to davenseparately and then convene only for kaddish and kedusha, but still having 6 men start shmoneh esreh together would be sufficient for a tefilla b’tzibur. According to this, we can interpret the Rambam’s words by their simple sense without having to try and explain his otherwise ambiguous language[5].
It is said in the name of Rav Shlomo Zalman Orbach[6]that if acting stringently in regards to this issue may in turn create a situation where some people won’t end up davening with a minyanat all, it is preferable to rely on the lenient opinions. Therefore I believe that in our minyan on campus we should rely on the ruling that it is enough to start shmoneh esreh with 6 men if it seems that otherwise the minyanmay fall apart before the end of davening.

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[1]Hilchot Tefilla 8:4. ואפילו היו מקצתן שכבר התפללו ויצאו ידי חובתן משלימין להם לעשרה והוא שיהיו רוב העשרה שלא התפללו[2]19:1.ועיקר התפלה בצבור הוא תפלת י"ח, דהיינו שיתפללו עשרה אנשים שהם גדולים ביחד, ולא כמו שחושבין ההמון שעיקר להתפלל בעשרה הוא רק משום לשמוע קדיש וקדושה וברכו, ולכן אינם מקפידים להתפלל ביחד רק שיהיה י' בבית הכנסת, והוא טעות גדול[3] On Shulchan Aruch 90 subparagraph 28[4]Igrot Moshe OC 1:28. See also responsa 29 and 30. [4.1] B'tzel Hachochmah 4:135[5]See Igrot Moshe ibid. who himself is aware of the problematic explanation he is offering to Rambam’s ruling. He ends responsum 28 with the abbreviation צ''ע meaning “this matter calls for further exploration”.[6]Halichot Shlomo 5:8