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كتاب المغازى
64  
Military Expeditions led by the Prophet (pbuh) (Al-Maghaazi)
(12)
Chapter
(12)
باب
Sahih al-Bukhari 4006

Narrated Abu Masud Al-Badri:

The Prophet (ﷺ) said, "A man's spending on his family is a deed of charity."

حَدَّثَنَا مُسْلِمٌ، حَدَّثَنَا شُعْبَةُ، عَنْ عَدِيٍّ، عَنْ عَبْدِ اللَّهِ بْنِ يَزِيدَ، سَمِعَ أَبَا مَسْعُودٍ الْبَدْرِيَّ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ ‏ "‏ نَفَقَةُ الرَّجُلِ عَلَى أَهْلِهِ صَدَقَةٌ ‏"‏‏.‏
Reference : Sahih al-Bukhari 4006
In-book reference : Book 64, Hadith 57
USC-MSA web (English) reference : Vol. 5, Book 59, Hadith 343
  (deprecated numbering scheme)