Muwatta Malik, Book 48, Hadith 8 (USC-MSA)

Yahya related to me from Malik from Yahya ibn Said from Ibn Shihab that the Messenger of Allah, may Allah bless him and grant him peace, stood up in the night and looked at the horizon of the sky. He said, "What treasures has the night opened? What trials have occurred? How many are dressed in this world and will be naked on the Day of Rising. Warn the women in their rooms."

وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ يَحْيَى بْنِ سَعِيدٍ، عَنِ ابْنِ شِهَابٍ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَامَ مِنَ اللَّيْلِ فَنَظَرَ فِي أُفُقِ السَّمَاءِ فَقَالَ ‏ "‏ مَاذَا فُتِحَ اللَّيْلَةَ مِنَ الْخَزَائِنِ وَمَاذَا وَقَعَ مِنَ الْفِتَنِ كَمْ مِنْ كَاسِيَةٍ فِي الدُّنْيَا عَارِيَةٌ يَوْمَ الْقِيَامَةِ أَيْقِظُوا صَوَاحِبَ الْحُجَرِ ‏" ‏ ‏.‏

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also referenced under: Book 48, Hadith 1662 (In-Book)