Riyad as-Salihin, Book 9, Hadith 1173 (In-Book)

'Aishah (May Allah be pleased with her) reported: The Prophet would sleep during the early part of night and stand in Salat during the latter part.[Al-Bukhari and Muslim].

وعنها أن النبي صلى الله عليه وسلم، كان ينام أول الليل، ويقوم آخره فيصلي‏.‏ ‏(‏‏(‏متفق عليه‏)‏‏)‏ ‏.‏

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