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كتاب الاستسقاء
15  
Invoking Allah for Rain (Istisqaa)
(19)
Chapter: To offer the Istisqa' prayer at the Musalla
(19)
باب الاِسْتِسْقَاءِ فِي الْمُصَلَّى
Sahih al-Bukhari 1027

Narrated `Abbad bin Tamim from his uncle who said:

"The Prophet (ﷺ) went out to the Musalla to offer the Istisqa' prayer, faced the Qibla and offered a two rak`at prayer and turned his cloak inside out." Narrated Abu Bakr, "The Prophet (ﷺ) put the right side of his cloak on his left side."

حَدَّثَنَا عَبْدُ اللَّهِ بْنُ مُحَمَّدٍ، قَالَ حَدَّثَنَا سُفْيَانُ، عَنْ عَبْدِ اللَّهِ بْنِ أَبِي بَكْرٍ، سَمِعَ عَبَّادَ بْنَ تَمِيمٍ، عَنْ عَمِّهِ، قَالَ خَرَجَ النَّبِيُّ صلى الله عليه وسلم إِلَى الْمُصَلَّى يَسْتَسْقِي، وَاسْتَقْبَلَ الْقِبْلَةَ فَصَلَّى رَكْعَتَيْنِ، وَقَلَبَ رِدَاءَهُ‏.‏ قَالَ سُفْيَانُ فَأَخْبَرَنِي الْمَسْعُودِيُّ عَنْ أَبِي بَكْرٍ قَالَ جَعَلَ الْيَمِينَ عَلَى الشِّمَالِ‏.‏
Reference : Sahih al-Bukhari 1027
In-book reference : Book 15, Hadith 22
USC-MSA web (English) reference : Vol. 2, Book 17, Hadith 139
  (deprecated numbering scheme)