Sahih al Bukhari 3710
Companions of the Prophet
حَدَّثَنَا الْحَسَنُ بْنُ مُحَمَّدٍ، حَدَّثَنَا مُحَمَّدُ بْنُ عَبْدِ اللَّهِ الأَنْصَارِيُّ، حَدَّثَنِي أَبِي عَبْدُ اللَّهِ بْنُ الْمُثَنَّى، عَنْ ثُمَامَةَ بْنِ عَبْدِ اللَّهِ بْنِ أَنَسٍ، عَنْ أَنَسٍ ـ رضى الله عنه أَنَّ عُمَرَ بْنَ الْخَطَّابِ، كَانَ إِذَا قَحَطُوا اسْتَسْقَى بِالْعَبَّاسِ بْنِ عَبْدِ الْمُطَّلِبِ، فَقَالَ اللَّهُمَّ إِنَّا كُنَّا نَتَوَسَّلُ إِلَيْكَ بِنَبِيِّنَا صلى الله عليه وسلم فَتَسْقِينَا، وَإِنَّا نَتَوَسَّلُ إِلَيْكَ بِعَمِّ نَبِيِّنَا فَاسْقِنَا. قَالَ فَيُسْقَوْنَ.
Narrated Anas:Whenever there was drought, `Umar bin Al-Khattab used to ask Allah for rain through Al-`Abbas bin `Abdul Muttalib, saying, "O Allah! We used to request our Prophet to ask You for rain, and You would give us. Now we request the uncle of our Prophet to ask You for rain, so give us rain." And they would be given rain
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