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كتاب الدعوات
80  
Invocations
(1)
Chapter: For every Prophet there is one invocation surely granted
(1)
باب وَلِكُلِّ نَبِيٍّ دَعْوَةٌ مُسْتَجَابَةٌ
Sahih al-Bukhari 6304

Narrated Abu Huraira:

Allah's Messenger (ﷺ) said, "For every prophet there is one (special invocation (that will not be rejected) with which he appeals (to Allah), and I want to keep such an invocation for interceding for my followers in the Hereafter."

حَدَّثَنَا إِسْمَاعِيلُ، قَالَ حَدَّثَنِي مَالِكٌ، عَنْ أَبِي الزِّنَادِ، عَنِ الأَعْرَجِ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏ "‏ لِكُلِّ نَبِيٍّ دَعْوَةٌ مُسْتَجَابَةٌ يَدْعُو بِهَا، وَأُرِيدُ أَنْ أَخْتَبِئَ دَعْوَتِي شَفَاعَةً لأُمَّتِي فِي الآخِرَةِ ‏"‏‏.‏
Reference : Sahih al-Bukhari 6304
In-book reference : Book 80, Hadith 1
USC-MSA web (English) reference : Vol. 8, Book 75, Hadith 317
  (deprecated numbering scheme)