Jami` at-Tirmidhi 1680
جامع الترمذي#1680Sahihحَدَّثَنَا أَحْمَدُ بْنُ مَنِيعٍ، حَدَّثَنَا يَحْيَى بْنُ زَكَرِيَّا بْنِ أَبِي زَائِدَةَ، حَدَّثَنَا أَبُو يَعْقُوبَ الثَّقَفِيُّ، حَدَّثَنَا يُونُسُ بْنُ عُبَيْدٍ، مَوْلَى مُحَمَّدِ بْنِ الْقَاسِمِ قَالَ بَعَثَنِي مُحَمَّدُ بْنُ الْقَاسِمِ إِلَى الْبَرَاءِ بْنِ عَازِبٍ أَسْأَلُهُ عَنْ رَايَةِ، رَسُولِ اللَّهِ صلى الله عليه وسلم فَقَالَ كَانَتْ سَوْدَاءَ مُرَبَّعَةً مِنْ نَمِرَةٍ . قَالَ أَبُو عِيسَى وَفِي الْبَابِ عَنْ عَلِيٍّ وَالْحَارِثِ بْنِ حَسَّانَ وَابْنِ عَبَّاسٍ . قَالَ أَبُو عِيسَى وَهَذَا حَدِيثٌ حَسَنٌ غَرِيبٌ لاَ نَعْرِفُهُ إِلاَّ مِنْ حَدِيثِ ابْنِ أَبِي زَائِدَةَ . وَأَبُو يَعْقُوبَ الثَّقَفِيُّ اسْمُهُ إِسْحَاقُ بْنُ إِبْرَاهِيمَ وَرَوَى عَنْهُ أَيْضًا عُبَيْدُ اللَّهِ بْنُ مُوسَى .
Narrated Yunus bin 'Ubaid: the freed salve of Muhammad bin Al-Qasim said: "Muhammad bin Al-Qasim sent me to Al-Bara' bin 'Azib to ask him about the flag of the Messenger of Allah (ﷺ). He said: 'It was a black square of Namirah.'" [Abu 'Eisa said:] There are narrations on this topic from 'Ali, Al-Harith bin Hassan, and Ibn 'Abbas. [Abu 'Eisa said:] This Hadith is Hasan Gharib, we don know know of it except from the report of Ibn Abi Za'idah. And Abu Ya'qub Ath-Thaqafi's name is Ishaq bin Ibrahim. 'Ubaidullah bin Musa also reports from him
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: 23:11