Sunan Abi Dawud 456
سنن أبي داود#456Sahihحَدَّثَنَا مُحَمَّدُ بْنُ دَاوُدَ بْنِ سُفْيَانَ، حَدَّثَنَا يَحْيَى، - يَعْنِي ابْنَ حَسَّانَ - حَدَّثَنَا سُلَيْمَانُ بْنُ مُوسَى، حَدَّثَنَا جَعْفَرُ بْنُ سَعْدِ بْنِ سَمُرَةَ، حَدَّثَنِي خُبَيْبُ بْنُ سُلَيْمَانَ، عَنْ أَبِيهِ، سُلَيْمَانَ بْنِ سَمُرَةَ عَنْ أَبِيهِ، سَمُرَةَ أَنَّهُ كَتَبَ إِلَى ابْنِهِ أَمَّا بَعْدُ فَإِنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم كَانَ يَأْمُرُنَا بِالْمَسَاجِدِ أَنْ نَصْنَعَهَا فِي دِيَارِنَا وَنُصْلِحَ صَنْعَتَهَا وَنُطَهِّرَهَا .
Samurah reported that he wrote (a letter) to his sons:After (praising Allah and blessing the Prophet) that: The Messenger of Allah (ﷺ) used to command us to build mosques in our localities and keep them well and clean
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
In-book reference: 2:66