Sahih al-Bukhari, Book 61, Hadith 49 (In-Book)

Narrated Al-Ju'aid bin `Abdur Rahman: I saw As-Sa'ib bin Yazid when he was ninety-four years old, quite strong and of straight figure. He said, "I know that I enjoyed my hearing and seeing powers only because of the invocation of Allah's Apostle. My aunt took me to him and said, 'O Allah's Messenger! My nephew is sick; will you invoke Allah for him?' So he invoked (Allah) for me."

حَدَّثَنِي إِسْحَاقُ، أَخْبَرَنَا الْفَضْلُ بْنُ مُوسَى، عَنِ الْجُعَيْدِ بْنِ عَبْدِ الرَّحْمَنِ، رَأَيْتُ السَّائِبَ بْنَ يَزِيدَ ابْنَ أَرْبَعٍ وَتِسْعِينَ جَلْدًا مُعْتَدِلاً فَقَالَ قَدْ عَلِمْتُ مَا مُتِّعْتُ بِهِ سَمْعِي وَبَصَرِي إِلاَّ بِدُعَاءِ رَسُولِ اللَّهِ صلى الله عليه وسلم، إِنَّ خَالَتِي ذَهَبَتْ بِي إِلَيْهِ فَقَالَتْ يَا رَسُولَ اللَّهِ إِنَّ ابْنَ أُخْتِي شَاكٍ فَادْعُ اللَّهَ‏.‏ قَالَ فَدَعَا لِي‏.‏

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