Sunan an-Nasa'i 1650
سنن النسائي#1650Sahihأَخْبَرَنَا زِيَادُ بْنُ أَيُّوبَ، قَالَ حَدَّثَنَا ابْنُ عُلَيَّةَ، قَالَ حَدَّثَنَا الْوَلِيدُ بْنُ أَبِي هِشَامٍ، عَنْ أَبِي بَكْرِ بْنِ مُحَمَّدٍ، عَنْ عَمْرَةَ، عَنْ عَائِشَةَ، قَالَتْ كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم يَقْرَأُ وَهُوَ قَاعِدٌ فَإِذَا أَرَادَ أَنْ يَرْكَعَ قَامَ قَدْرَ مَا يَقْرَأُ إِنْسَانٌ أَرْبَعِينَ آيَةً .
It was narrated that Aishah said:"The Messenger of Allah (ﷺ) used to recite sitting, and when he wanted to bow he would stand up for as long as it takes a person to recite forty verses
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: 20:53