Sunan Abi Dawud 606
سنن أبي داود#606Sahihحَدَّثَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، وَيَزِيدُ بْنُ خَالِدِ بْنِ مَوْهَبٍ، - الْمَعْنَى - أَنَّ اللَّيْثَ، حَدَّثَهُمْ عَنْ أَبِي الزُّبَيْرِ، عَنْ جَابِرٍ، قَالَ اشْتَكَى النَّبِيُّ صلى الله عليه وسلم فَصَلَّيْنَا وَرَاءَهُ وَهُوَ قَاعِدٌ وَأَبُو بَكْرٍ يُكَبِّرُ لِيُسْمِعَ النَّاسَ تَكْبِيرَهُ ثُمَّ سَاقَ الْحَدِيثَ .
Jabir said :when the prophet (ﷺ) became seriously ill, we prayed behind him while he was sitting and Abu Bakr was calling “Allah is most great “ to cause the people to hear the TAKBIR. Then he (the narrators) narrated the rest of the tradition
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: 2:216