As Salat is a compulsion on a believer so is its offering in congregation. Islam is a religion which does not entertain individualism at any level. Be it in war or peace, offering of Salat or payment of Zakat. The prophet of ALLAH taught the ummah to reside in group rather than solitarily, perform the duties of Islam in assembly rather than individually.

The Salat, a foremost obligation on a Muslim, is to be offered in congregation. Just to drive the people towards congregation ALLAH has promised more reward in congregation rather than performing in isolation. In one hadith Prophet PBUH said "Offering the prayer in congregation carries 27 times greater reward than offering it alone individually." (Bukhari, Muslim). This reward rises exponentially if the person offers Salat in Makkah (Masjid-e-haram), Madinah (Masid-e-nabawi) and Jerusalem (Masjid-e-Aqsa). Similarly there is another hadith in which Prophet PBUH said "If the people come to know of the great rewards and benefits of the congregational prayer, they would never stay back but would rush to the masjid for it. The first row merits the highest reward. Two persons praying together get greater rewards than the same praying individually, the rule being that, the bigger the congregation the higher it's worth in the sight of ALLAH." (Abu Dawud)

Abdullah ibn Maktoom, a companion of the Prophet PBUH who was blind, once came to the messenger of ALLAH and asked him, "Oh Messenger of ALLAH, I am blind, live at a distance, and do not have someone to guide him to the mosque, so can't you give me consent to pray at home?" He said "Do you hear the call (adhan)?" Ibn Maktoom replied "Yes". The Prophet PBUH then said "I cannot find an excuse for you." This clearly proves when a blind was not given consent to pray at home then one who is physically blessed and with no abnormalities, can ever think of abstaining himself from congregation.

The wrath of staying away from congregational prayers could be best understood by this hadith. The Prophet of ALLAH said "Nothing is harder on the hypocrites than the Isha and Fajr prayer; had they known of the great rewards that ALLAH would bestow for those prayers they would never had missed them even if they had to come to the masjid on their knees" Then he said, "I wish I should tell a Mua'dhin to pronounce the iqamah and appoint someone as Imam in my place, and I should myself go and set fire to the houses of those who do not come out even after hearing the adhan.(Bukhari, Muslim). This should be sufficient for us to understand the gravity of leaving the congregation.

Mentioned below are collections of few traditions of Prophet PBUH which reveal the rewards of congregational prayers
• Narrated Anas, Prophet PBUH said: "The person who offers his prayers continuously for 40 days without missing the first takbeer, is granted a two-fold immunity by ALLAH: immunity from Hell-fire and immunity from hypocrisy.(Tirmidhi)
• Narrated Usman, that he heard the Prophet PBUH saying "The person who observes the Isha prayer in congregation, will have the reward and blessings of staying up half the night in prayer, and the one who observes the Fajr prayer in congregation will have the reward and blessings of staying up the whole night in prayer." (Tirmidhi)
• Prophet PBUH said "Give good news to those who go to the masjid in the darkness of the night to offer the prayer in congregation that on the Day of Judgment they will be provided with a perfect light." (Tirmidhi)

The prophet PBUH said: "O Muslims! ALLAH has prescribed paths of right guidance for you, among which, is the offering of the daily prayers in congregation in the masjid. If you start saying your prayers individually at home, as so-and-so do, you will be forsaking the Sunnah of your Prophet, and if you forsake the Sunnah of your Prophet, you will certainly be going astray." (Muslim).