Sunan Abi Dawud 4667
سنن أبي داود#4667Sahihحَدَّثَنَا مُسْلِمُ بْنُ إِبْرَاهِيمَ، حَدَّثَنَا الْقَاسِمُ بْنُ الْفَضْلِ، عَنْ أَبِي نَضْرَةَ، عَنْ أَبِي سَعِيدٍ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " تَمْرُقُ مَارِقَةٌ عِنْدَ فُرْقَةٍ مِنَ الْمُسْلِمِينَ يَقْتُلُهَا أَوْلَى الطَّائِفَتَيْنِ بِالْحَقِّ " .
Abu Sa’id reported the Messenger of Allah (May peace be upon him) as saying:In the event of the dissension among Muslims an emerging sect will emerge ; one of the two parties that is nearer to the truth will kill it
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: 42:72