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bukhari:1010al-Ḥasan b. Muḥammad > Muḥammad b. ʿAbdullāh al-Anṣārī > Abū ʿAbdullāh b. al-Muthanná > Thumāmah b. ʿAbdullāh b. Anas > Anas > ʿUmar

Whenever drought threatened them, ʿUmar bin Al-Khattab, used to ask Al-Abbas bin ʿAbdul Muttalib to invoke Allah for rain. He used to say, "O Allah! We used to ask our Prophet to invoke You for rain, and You would bless us with rain, and now we ask his uncle to invoke You for rain. O Allah ! Bless us with rain."(1) And so it would rain.  

البخاري:١٠١٠حَدَّثَنَا الْحَسَنُ بْنُ مُحَمَّدٍ قَالَ حَدَّثَنَا مُحَمَّدُ بْنُ عَبْدِ اللَّهِ الأَنْصَارِيُّ قَالَ حَدَّثَنِي أَبِي عَبْدُ اللَّهِ بْنُ الْمُثَنَّى عَنْ ثُمَامَةَ بْنِ عَبْدِ اللَّهِ بْنِ أَنَسٍ عَنْ أَنَسٍ أَنَّ عُمَرَ بْنَ الْخَطَّابِ ؓ كَانَ إِذَا قَحَطُوا اسْتَسْقَى بِالْعَبَّاسِ بْنِ عَبْدِ الْمُطَّلِبِ فَقَالَ

اللَّهُمَّ إِنَّا كُنَّا نَتَوَسَّلُ إِلَيْكَ بِنَبِيِّنَا فَتَسْقِينَا وَإِنَّا نَتَوَسَّلُ إِلَيْكَ بِعَمِّ نَبِيِّنَا فَاسْقِنَا قَالَ فَيُسْقَوْنَ  


See similar narrations below:

Collected by Bukhārī, Suyūṭī
bukhari:3710al-Ḥasan b. Muḥammad > Muḥammad b. ʿAbdullāh al-Anṣārī > Abū ʿAbdullāh b. al-Muthanná > Thumāmah b. ʿAbdullāh b. Anas > Anas

Whenever there was drought, ʿUmar bin Al-Khattab used to ask Allah for rain through Al-ʿAbbas bin ʿAbdul 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."  

البخاري:٣٧١٠حَدَّثَنَا الْحَسَنُ بْنُ مُحَمَّدٍ حَدَّثَنَا مُحَمَّدُ بْنُ عَبْدِ اللَّهِ الأَنْصَارِيُّ حَدَّثَنِي أَبِي عَبْدُ اللَّهِ بْنُ الْمُثَنَّى عَنْ ثُمَامَةَ بْنِ عَبْدِ اللَّهِ بْنِ أَنَسٍ عَنْ أَنَسٍ ؓ أَنَّ عُمَرَ بْنَ الْخَطَّابِ كَانَ إِذَا قَحَطُوا اسْتَسْقَى بِالْعَبَّاسِ بْنِ عَبْدِ الْمُطَّلِبِ فَقَالَ

اللَّهُمَّ إِنَّا كُنَّا نَتَوَسَّلُ إِلَيْكَ بِنَبِيِّنَا ﷺ فَتَسْقِينَا وَإِنَّا نَتَوَسَّلُ إِلَيْكَ بِعَمِّ نَبِيِّنَا فَاسْقِنَا قَالَ فَيُسْقَوْنَ  

suyuti:2-142bAnas
Request/Fix translation

  

السيوطي:٢-١٤٢b

"عن أَنَس أَنَّ عُمَرَ بْنَ الخَطَّابِ كَانَ إِذَا قُحِطُوا اسْتَسْقَى بِالْعَبَّاسِ بْنِ عَبْدِ الْمُطَّلبِ، فَقَالَ: اللَّهُمَّ إِنَّا كُنَّا نَتَوَسَّلُ إِلَيْكَ بنَبِيِّنَا فَتَسْقِيَنَا، وَإِنَّا نَتَوسَّلُ إِلَيْكَ بَعَمِّ نَبِيِّنَا فَاسْقِنَا، فَيُسْقَوْنَ".

. . . .  

خ, وابن خزيمة، وأبو عوانة، [حب] ابن حبّان