صَحِيحُ مُسْلِمٍ
Sahih Muslim 649 a
The Book of Mosques and Places of Prayer
The virtue of prayer in congregation, and clarifying the stern warning against staying away from it, and that it is fard kifayah
حَدَّثَنَا يَحْيَى بْنُ يَحْيَى، قَالَ قَرَأْتُ عَلَى مَالِكٍ عَنِ ابْنِ شِهَابٍ، عَنْ سَعِيدِ بْنِ الْمُسَيَّبِ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ صَلاَةُ الْجَمَاعَةِ أَفْضَلُ مِنْ صَلاَةِ أَحَدِكُمْ وَحْدَهُ بِخَمْسَةٍ وَعِشْرِينَ جُزْءًا .
Abu Huraira reported Allah's Messenger (ﷺ) as saying: Prayer said in a congregation is twenty-five degrees more excellent than prayer said by a single person.
Sahih Muslim, 649 aSahihصحيح