AHMAD 6372:
from Nāfiʿ —
[Machine] "Narrated Ibn Umar that he used to say: 'Whoever prays at night, let him make Witr as his last prayer. For indeed, the Messenger of Allah ﷺ commanded that. And when dawn comes, all the night prayers and Witr are gone. For indeed, the Messenger of Allah ﷺ said: 'Perform Witr before dawn.'
أحمد ٦٣٧٢:
عن نافع —
أَنَّ ابْنَ عُمَرَ كَانَ يَقُولُ مَنْ صَلَّى بِاللَّيْلِ فَلْيَجْعَلْ آخِرَ صَلَاتِهِ وِتْرًا فَإِنَّ رَسُولَ اللهِ ﷺ أَمَرَ بِذَلِكَ فَإِذَا كَانَ الْفَجْرُ فَقَدْ ذَهَبَتْ كُلُّ صَلَاةِ اللَّيْلِ وَالْوَتْرُ فَإِنَّ رَسُولَ اللهِ ﷺ قَالَ أَوْتِرُوا قَبْلَ الْفَجْرِ
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