Sunan an-Nasa'i 797
سنن النسائي#797Sahihأَخْبَرَنَا مَحْمُودُ بْنُ غَيْلاَنَ، قَالَ حَدَّثَنِي أَبُو دَاوُدَ، قَالَ أَنْبَأَنَا شُعْبَةُ، عَنْ مُوسَى بْنِ أَبِي عَائِشَةَ، قَالَ سَمِعْتُ عُبَيْدَ اللَّهِ بْنَ عَبْدِ اللَّهِ، يُحَدِّثُ عَنْ عَائِشَةَ، رضى الله عنها أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم أَمَرَ أَبَا بَكْرٍ أَنْ يُصَلِّيَ بِالنَّاسِ قَالَتْ وَكَانَ النَّبِيُّ صلى الله عليه وسلم بَيْنَ يَدَىْ أَبِي بَكْرٍ فَصَلَّى قَاعِدًا وَأَبُو بَكْرٍ يُصَلِّي بِالنَّاسِ وَالنَّاسُ خَلْفَ أَبِي بَكْرٍ .
It was narrated from Aisha may Allah be pleased with her, that the Messenger of Allah (ﷺ) told Abu Bakr to lead the people in prayer. She said:"The Prophet was in front of Abu Bakr and he prayed sitting down, and Abu Bakr was leading the people in prayer, and the people were behind Abu Bakr
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: 10:21