Sahih al-Bukhari 3188
صحيح البخاري#3188Sahihحَدَّثَنَا سُلَيْمَانُ بْنُ حَرْبٍ، حَدَّثَنَا حَمَّادٌ، عَنْ أَيُّوبَ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ ـ رضى الله عنهما ـ قَالَ سَمِعْتُ النَّبِيَّ صلى الله عليه وسلم يَقُولُ " لِكُلِّ غَادِرٍ لِوَاءٌ يُنْصَبُ لِغَدْرَتِهِ ".
Narrated Ibn `Umar:The Prophet (ﷺ) said, "Every betrayer will have a flag which will be fixed on the Day of Resurrection, and the flag's prominence will be made in order to show the betrayal he committed
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:
Every narration in Sahih al-Bukhari is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 58:29