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
Sahih Muslim 1893 a

It has been narrated on the authority of Abu Mas'ud al-Ansari who said:

A man came to the Messenger of Allah (ﷺ) and said: My riding beast has been killed, so give me some animal to ride upon. He (the Holy Prophet) said: I have none with me. A man said: Messenger of Allah, I can guide him to one who will provide him with a riding beast. The Messenger of Allah (ﷺ) said: One who guides to something good has a reward similar to that of its doer.
وَحَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، وَأَبُو كُرَيْبٍ وَابْنُ أَبِي عُمَرَ - وَاللَّفْظُ لأَبِي كُرَيْبٍ - قَالُوا حَدَّثَنَا أَبُو مُعَاوِيَةَ، عَنِ الأَعْمَشِ، عَنْ أَبِي عَمْرٍو الشَّيْبَانِيِّ، عَنْ أَبِي مَسْعُودٍ الأَنْصَارِيِّ، قَالَ جَاءَ رَجُلٌ إِلَى النَّبِيِّ صلى الله عليه وسلم فَقَالَ إِنِّي أُبْدِعَ بِي فَاحْمِلْنِي فَقَالَ ‏"‏ مَا عِنْدِي ‏"‏ ‏.‏ فَقَالَ رَجُلٌ يَا رَسُولَ اللَّهِ أَنَا أَدُلُّهُ عَلَى مَنْ يَحْمِلُهُ فَقَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏"‏ مَنْ دَلَّ عَلَى خَيْرٍ فَلَهُ مِثْلُ أَجْرِ فَاعِلِهِ ‏"‏ ‏.‏
Reference : Sahih Muslim 1893a
In-book reference : Book 33, Hadith 195
USC-MSA web (English) reference : Book 20, Hadith 4665
  (deprecated numbering scheme)