The Book of Qiyam Al-Lail (The Night Prayer) and Voluntary Prayers During the Day
20/18. Chapter:
What is done when one begins the prayer standing and mentioning the differences with those who reported from 'Aisha concerning it
Sunan an-Nasai
أَخْبَرَنَا 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."
Reference : Sunan an-Nasa'i 1650In-book reference : Book 20, Hadith 53English translation : Vol. 2, Book 20, Hadith 1651