Sunan an-Nasa'i, Book 20, Hadith 19 (In-Book)

It was narrated that Masruq said: "I said to 'Aishah: 'Which deed was most beloved to the Messenger of Allah?' She said: 'That which was done persistently.' I said: 'At what part of the night did he pray Qiyam?' She said: 'When he heard the rooster.'"

أَخْبَرَنَا مُحَمَّدُ بْنُ إِبْرَاهِيمَ الْبَصْرِيُّ، عَنْ بِشْرٍ، - هُوَ ابْنُ الْمُفَضَّلِ - قَالَ حَدَّثَنَا شُعْبَةُ، عَنْ أَشْعَثَ بْنِ سُلَيْمٍ، عَنْ أَبِيهِ، عَنْ مَسْرُوقٍ، قَالَ قُلْتُ لِعَائِشَةَ أَىُّ الأَعْمَالِ أَحَبُّ إِلَى رَسُولِ اللَّهِ صلى الله عليه وسلم قَالَتِ الدَّائِمُ ‏.‏ قُلْتُ فَأَىُّ اللَّيْلِ كَانَ يَقُومُ قَالَتْ إِذَا سَمِعَ الصَّارِخَ ‏.‏

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