The Prophet, sallallahu ^alayhi wa sallam, encouraged performing the congregational prayer. He ordered the people to pray the five (5) prayers in congregation in a way that any one who wants to pray in congregation can easily find the place to do so. When people gather in obedience to Allah, great benefits do occur.
The Prophet, sallallahu ^alayhi wa sallam, said:
صَلاَةُ الْجَمَاعَةِ تَفْضُلُ صَلاَةَ الْفَذِّ بِسَبْعٍ وَعِشْرِينَ دَرَجَة
Salatul-jama^ati tafdulu salatal-fadhdhi bisab^iw wa ^ishrina darajah.
Which means: “The congregational prayer has 27 times more reward (thawab) than the prayer of an individual.” (Related by Ibn Majah, at-Tirmidhiyy, and Ahmad ibn Hanbal.)
Praying every obligatory prayer in congregation is a communal obligation upon the free, residing, pubescent, and unexcused men.
How to Pray the Congregational Prayer (Jama^ah):
One of the people who want to pray the congregational prayer steps forward to lead the others in prayer. He is called the leader (imam). It is better if the imam is the most knowledgeable among them and the one who recites Qur’an the best.
The rest of the people stand behind the imam in straight rows, leaving no spaces in between each other. Then the imam says the opening Allahu Akbar (takbiratul-ihram). Then other people say their opening Allahu Akbar coupled with the intention. The intention means that every one of them says in one’s heart, for example, while saying Allahu Akbar with one’s tongue: “I now intend to pray the obligatory ^Asr prayer in congregation.”
The imam says all the sayings of Allahu Akbar, sami^allahu liman hamidah, and as-salamu ^alaykum out loud in all the prayers. If it is a loud prayer, the imam also says the Fatihah, Amin, and the Surah after it out loud in the first two rak^ahs. The follower says Amin out loud, but he does not recite the Surah after the Fatihah in the loud prayer; rather, he does this only in the soft prayer.
The Conditions of Following the Imam in Prayer:
Everyone who follows an imam while performing prayer—the Jumu^ah Prayer or other prayers–must fulfill the following obligations:
1. The follower (ma’mum) must not be ahead of his imam in the standing position or in saying the opening Allahu akbar. The prayer of the follower is invalid if he says his opening Allahu akbar during that of the imam. Doing other actions at the same time as the imam in other parts of the prayer is disliked (makruh), with the exception of saying: “Amin ”.
2. It is unlawful (haram) for the follower (ma’mum) to precede the imam by one integral of action. One’s prayer is invalidated by inexcusably preceding the imam by two consecutive integrals of action, whether both are long or one is long and the other is short. Similarly, the ma’mum invalidates his prayer if he lags behind the imam by two integrals of action, despite an excuse. If the ma’mum stays behind to finish the Fatihah and during this time the imam has finished his ruku^ and two prostrations, and has sat for the tashahhud or stood up for the following rak^ah, then the ma’mum must stop reciting the Fatihah and be in unison with his imam. In addition to this, the ma’mum must perform a rak^ah after the closing salam of the imam. However, if the ma’mum finishes reciting the Fatihah before the imam has sat for the tashahhud or stood up for another rak^ah, then the ma’mum follows his own order until he catches up with the imam.
3. The follower must know the movements of his imam.
4. The follower must be with his imam in a mosque (masjid), or else within 300 cubits.
5. The follower must not have any barrier between him and the imam which prevents him from reaching the imam.
6. The follower must have the format of his prayer agree with the format of the imam’s prayer. For example, it is invalid for the performer of the daily obligatory prayer to follow the performer of the Funeral Prayer (Salatul-Janazah).
7. The follower must not disagree enormously with his imam in a recommended act (sunnah), like the sitting for the first tashahhud. If the imam does it or leaves it, then the ma’mum does it with the imam or stands up with him.
In the Jumu^ah Prayer, the follower must have the intention to follow the imam while saying the opening Allahu akbar, and in other prayers, before following the imam. If the ma’mum was performing the Jumu^ah Prayer without having the intention to follow the imam within the opening Allahu akbar, his prayer would be invalid. In other than the Jumu^ah Prayer, the intention to follow the imam must be in the heart before following the imam in his moves. Following the imam in his moves without the intention to follow invalidates the ma’mum’s prayer. However, if one’s moves agree with the imam’s moves accidentally and unintentionally, one does not invalidate one’s prayer.
