كتاب الإمارة
33
The Book on Government
(38)
Chapter: The virtue of helping the warrior who is fighting in the cause of Allah with mounts etc., and looking after his family in his absence
(38)
باب فَضْلِ إِعَانَةِ الْغَازِي فِي سَبِيلِ اللَّهِ بِمَرْكُوبٍ وَغَيْرِهِ وَخِلاَفَتِهِ فِي أَهْلِهِ بِخَيْرٍ

The above tradition has been narrated on the authority of Khalid al- Juhani who said:

The Prophet of Allah (ﷺ) said: He who equips a warrior in the way of Allah (is like one who dctually fights) aud he who looks after the family of a warrior in the way of Allah in fact participated in the battle.
حَدَّثَنَا أَبُو الرَّبِيعِ الزَّهْرَانِيُّ، حَدَّثَنَا يَزِيدُ، - يَعْنِي ابْنَ زُرَيْعٍ - حَدَّثَنَا حُسَيْنٌ، الْمُعَلِّمُ حَدَّثَنَا يَحْيَى بْنُ أَبِي كَثِيرٍ، عَنْ أَبِي سَلَمَةَ بْنِ عَبْدِ الرَّحْمَنِ، عَنْ بُسْرِ بْنِ سَعِيدٍ، عَنْ زَيْدِ بْنِ خَالِدٍ الْجُهَنِيِّ، قَالَ قَالَ نَبِيُّ اللَّهِ صلى الله عليه وسلم ‏ "‏ مَنَ جَهَّزَ غَازِيًا فَقَدْ غَزَا وَمَنْ خَلَفَ غَازِيًا فِي أَهْلِهِ فَقَدْ غَزَا ‏"‏ ‏.‏
Reference : Sahih Muslim 1895 b
In-book reference : Book 33, Hadith 199
USC-MSA web (English) reference : Book 20, Hadith 4669
  (deprecated numbering scheme)