Sunan Abi Dawud 4876
سنن أبي داود#4876Sahihحَدَّثَنَا مُحَمَّدُ بْنُ عَوْفٍ، حَدَّثَنَا أَبُو الْيَمَانِ، حَدَّثَنَا شُعَيْبٌ، حَدَّثَنَا عَبْدُ اللَّهِ بْنُ أَبِي حُسَيْنٍ، حَدَّثَنَا نَوْفَلُ بْنُ مُسَاحِقٍ، عَنْ سَعِيدِ بْنِ زَيْدٍ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ " إِنَّ مِنْ أَرْبَى الرِّبَا الاِسْتِطَالَةَ فِي عِرْضِ الْمُسْلِمِ بِغَيْرِ حَقٍّ " .
Narrated Sa'id ibn Zayd: The Prophet (ﷺ) said: The most prevalent kind of usury is going to lengths in talking unjustly against a Muslim's honour
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:
Al-AlbaniSahih
Muhammad Muhyi Al-Din Abdul HamidSahih
Shuaib Al ArnautSahih
Zubair Ali ZaiIsnaad Sahih
In-book reference: 43:104