‏الصلاة : Hadeeth No:1365 Ibn Umar reported Allaah's Messenger (sallAllaahu alayhi wa sallam) assaying: Prayer said in a congregation is twenty-seven degrees more excellent than prayer said by a single person....

‏الصلاة : Hadeeth No:937 Jabir reported: 'Mu'adh b jabal al-Ansari led his companions in the night prayer and prolonged it for them. A person amongst us said prayer (after having separated himself from the congregation). Mu'adh was informed of this, and he remarked that he wasa hypocrite. When it (the remark) was conveyed t...