Sunan an-Nasa'i, Volume 1, Book 6, Hadith 537 (DarusSalam)

It was narrated that 'Aishah the Mother of the Believers said: "The Prophet delayed the prayer one night until most of the night had passed and the people in the Masjid had gone home to sleep, then he went out and prayed, and said: 'This is indeed its (prayer) time, were it not that I would impose too much difficulty on my Ummah.'"

أَخْبَرَنِي إِبْرَاهِيمُ بْنُ الْحَسَنِ، قَالَ حَدَّثَنَا حَجَّاجٌ، قَالَ قَالَ ابْنُ جُرَيْجٍ ح وَأَخْبَرَنِي يُوسُفُ بْنُ سَعِيدٍ، قَالَ حَدَّثَنَا حَجَّاجٌ، عَنِ ابْنِ جُرَيْجٍ، قَالَ أَخْبَرَنِي الْمُغِيرَةُ بْنُ حَكِيمٍ، عَنْ أُمِّ كُلْثُومٍ ابْنَةِ أَبِي بَكْرٍ، أَنَّهَا أَخْبَرَتْهُ عَنْ عَائِشَةَ أُمِّ الْمُؤْمِنِينَ، قَالَتْ أَعْتَمَ النَّبِيُّ صلى الله عليه وسلم ذَاتَ لَيْلَةٍ حَتَّى ذَهَبَ عَامَّةُ اللَّيْلِ وَحَتَّى نَامَ أَهْلُ الْمَسْجِدِ ثُمَّ خَرَجَ فَصَلَّى وَقَالَ ‏ "‏ إِنَّهُ لَوَقْتُهَا لَوْلاَ أَنْ أَشُقَّ عَلَى أُمَّتِي ‏" ‏ ‏.‏

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also referenced under: Book 6, Hadith 541 (In-Book)