In Shemos (5:6), it states, תבן לתת תאסיפון לא ללקוט לעם, "You shall no longer give straw..." Why is there an extra 'א in the word תאסיפון?
Rebbe Dovid of Lelov zt'l explained that Pharaoh decreed, תאסיפון לא, that Yidden may no longer gather. Every Shabbos, in Mitzrayim, Yidden would gather and discuss emunah. Pharaoh understood how much they gain when they come together, so he decreed תאסיפון לא that they may not gather anymore.
(Rebbe Dovid Lelover zt'l said that he is sure that when Moshiach arrives, Moshe Rabbeinu will greet him and thank him for explaining the correct reason he added the ף"אל in this word.)
Indeed, this is one of the benefits of davening with a minyan. It is where we meet with good Yidden and strengthen our emunah.
Another benefit of a minyan is that Hashem is there wherever there is a minyan. The Baal HaTanya (letter 23) writes, "I was taught by my rebbes [the Baal Shem Tov zt'l and the Magid of Mezritzh zt'l] that if a malach were to stand in the presence of a gathering of ten Yidden, even if there were no words of Torah spoken between them, a boundless and infinite fear would befall that malach on account of the Shechinah that resides over them, and he would become utterly nullified."
Perhaps the most significant benefit of all is that the tefillos are answered.
The Gemara (Brachos 7-8) tells the following story:
Rav Yitzchak asked Rav Nachman, "Why didn’t you come to the beis kneses to daven?"
"I couldn’t. I was weak."
"You should have asked ten people to come to your home so you could daven in your home with a minyan."
"מילתא לי טריחא – it was hard for me to do that."
"You should have asked the gabai of the beis knesses to let you know when the tzibbur is about to say Shemonah Esrei, so you could begin Shemonah Esrei together with them."
Rav Nachman asked Rav Yitzchak, "Why is davening with a minyan so important?"
Rav Yitzchak replied in the name of Reb Shimon bar Yochai: "It states (Tehillim 69:14), רצון עת 'ה לך תפילתי ואני 'I pray to you at a desired time.' When is that desired time? It's when the tzibur is davening."
It is an eis ratzon, and there is a greater likelihood that his tefillos will be answered.
The Beis Aharon zy'a writes, "Tefillah b'tzibur can help for all matters, just like the tefillos of the tzaddik hador."
The Chofetz Chaim (Nidchai Yisrael 5) writes:
"Due to our many sins, some people daven at home during the weekdays because they don't appreciate the great mitzvah of davening with a minyan. Therefore, I feel obligated to write before all about this great mitzvah. When one davens with a minyan, in addition to increasing Hashem's honor, as it states (Mishlei 14:28) מלך הדרת עם ברב, 'In a multitude of people is the king's glory,' additionally, when he davens with a minyan, he performs several other mitzvos, such as answering Barchu and Amen yehei shmei rabba, and Kedushah. These are so great and very precious before Hashem. These arouse Hashem's love for Yisrael, reminding Hashem of their galus and hastens their redemption. It states in Midrash 'Tell My children what I do at tefillas Shacharis when they say ת"צבאו 'ה קדוש קדוש קדוש. Teach them to raise their eyes to heaven...and they should lift their heels and their bodies when they sanctify Me because the pleasure I have when they raise their eyes to me, and I look into their eyes is more than all other pleasure that I have from the world. At this time, I grab onto My throne of glory, where the image of Yaakov is engraved, and I hug and kiss it, and I remember their galus, and I hasten the redemption.' ... Also, Chazal say, 'Whoever answers Amen yehei shmei rabba with all his concentration, I will rip up harsh decrees.' In addition, when one davens with a minyan, he performs tens of mitzvos each day because he will answer amen to all the brachos he hears... Another great benefit is that when he davens with a tzibur, his tefillah is more likely to be answered. As the Gemara (Brachos 8) states, "When is it an eis ratzon for tefillah? It is when the tzibur davens."
