Sahih Muslim
The Book of Mosques and Places of Prayer
Hadith #308
5.308
وَحَدَّثَنَا عَبْدُ اللَّهِ بْنُ مَسْلَمَةَ بْنِ قَعْنَبٍ، حَدَّثَنَا أَفْلَحُ، عَنْ أَبِي بَكْرِ بْنِ مُحَمَّدِ بْنِ عَمْرِو بْنِ حَزْمٍ، عَنْ سَلْمَانَ الأَغَرِّ، عَنْ أَبِي هُرَيْرَةَ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " صَلاَةُ الْجَمَاعَةِ تَعْدِلُ خَمْسًا وَعِشْرِينَ مِنْ صَلاَةِ الْفَذِّ " .
Abu Huraira reported Allah's Messenger (ﷺ) as saying:Prayer said in a congregation is equivalent to twenty-five (prayers) as compared with the prayer said by a single person