Sunan Abi Dawud, Hadith 1450 ⓘ

Abu Hurairah reported the Prophet as saying: No people get together in a house of the houses of Allah (i.e. a mosque), reciting the Book of Allah, and learning it together among themselves, but calmness (sakinah) comes down to them, (Divine) mercy covers them (from above), and the angels surround them, and Allah makes a mention of them among those who are with Him.

حَدَّثَنَا عُثْمَانُ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا أَبُو مُعَاوِيَةَ، عَنِ الأَعْمَشِ، عَنْ أَبِي صَالِحٍ، عَنْ أَبِي هُرَيْرَةَ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ ‏ "‏ مَا اجْتَمَعَ قَوْمٌ فِي بَيْتٍ مِنْ بُيُوتِ اللَّهِ تَعَالَى يَتْلُونَ كِتَابَ اللَّهِ وَيَتَدَارَسُونَهُ بَيْنَهُمْ إِلاَّ نَزَلَتْ عَلَيْهِمُ السَّكِينَةُ وَغَشِيَتْهُمُ الرَّحْمَةُ وَحَفَّتْهُمُ الْمَلاَئِكَةُ وَذَكَرَهُمُ اللَّهُ فِيمَنْ عِنْدَهُ ‏" ‏ ‏.‏