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.”