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كتاب الجهاد والسير
56  
Fighting for the Cause of Allah (Jihaad)
(1)
Chapter: The superiority of Jihad
(1)
باب فَضْلُ الْجِهَادِ وَالسِّيَرِ
Sahih al-Bukhari 2784

Narrated `Aisha:

(That she said), "O Allah's Messenger (ﷺ)! We consider Jihad as the best deed. Should we not fight in Allah's Cause?" He said, "The best Jihad (for women) is Hajj-Mabrur (i.e. Hajj which is done according to the Prophet's tradition and is accepted by Allah).

حَدَّثَنَا مُسَدَّدٌ، حَدَّثَنَا خَالِدٌ، حَدَّثَنَا حَبِيبُ بْنُ أَبِي عَمْرَةَ، عَنْ عَائِشَةَ بِنْتِ طَلْحَةَ، عَنْ عَائِشَةَ ـ رضى الله عنها ـ أَنَّهَا قَالَتْ يَا رَسُولَ اللَّهِ تُرَى الْجِهَادَ أَفْضَلَ الْعَمَلِ، أَفَلاَ نُجَاهِدُ قَالَ ‏ "‏ لَكِنَّ أَفْضَلَ الْجِهَادِ حَجٌّ مَبْرُورٌ ‏"‏‏.‏
Reference : Sahih al-Bukhari 2784
In-book reference : Book 56, Hadith 3
USC-MSA web (English) reference : Vol. 4, Book 52, Hadith 43
  (deprecated numbering scheme)