Sahih Muslim , Book 48, Hadith 78 (In-Book)

This hadith has been transmitted on the authority of al-Bara' b. 'Azib that Allah's Messenger said to a person: O, so and so, as you go to your bed; the rest of the hadith is the same but with this variation of wording that he said:" Thine Apostle whom Thou sent." If you die that night you would die on Fitra and if you get up in the morning you would get up with a bliss.

حَدَّثَنَا يَحْيَى بْنُ يَحْيَى، أَخْبَرَنَا أَبُو الأَحْوَصِ، عَنْ أَبِي إِسْحَاقَ، عَنِ الْبَرَاءِ بْنِ، عَازِبٍ قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم لِرَجُلٍ ‏"‏ يَا فُلاَنُ إِذَا أَوَيْتَ إِلَى فِرَاشِكَ ‏"‏ ‏.‏ بِمِثْلِ حَدِيثِ عَمْرِو بْنِ مُرَّةَ غَيْرَ أَنَّهُ قَالَ ‏"‏ وَبِنَبِيِّكَ الَّذِي أَرْسَلْتَ ‏.‏ فَإِنْ مُتَّ مِنْ لَيْلَتِكَ مُتَّ عَلَى الْفِطْرَةِ وَإِنْ أَصْبَحْتَ أَصَبْتَ خَيْرًا ‏"‏ ‏.‏

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