Sunan an-Nasa'i 3562
It was narrated that Abu Hurairah said:
"The Messenger of Allah said: 'There is goodness tied to the forelocks of horses until the Day of Resurrection. And horses are of three types: Those that bring reward to man, those that are a means of protection for a man, and those that are a burden (of sin) for a man. As for those that bring reward, they are kept for the cause of Allah and for Jihad. No fodder enters their stomach but for everything that enters their stomachs, reward is written for him, even if he puts them out to pasture.'" And he quoted the Hadith.
أَخْبَرَنَا عَمْرُو بْنُ يَحْيَى بْنِ الْحَارِثِ، قَالَ حَدَّثَنَا مَحْبُوبُ بْنُ مُوسَى، قَالَ حَدَّثَنَا أَبُو إِسْحَاقَ، - يَعْنِي الْفَزَارِيَّ - عَنْ سُهَيْلِ بْنِ أَبِي صَالِحٍ، عَنْ أَبِيهِ، عَنْ أَبِي هُرَيْرَةَ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏
"‏ الْخَيْلُ مَعْقُودٌ فِي نَوَاصِيهَا الْخَيْرُ إِلَى يَوْمِ الْقِيَامَةِ الْخَيْلُ ثَلاَثَةٌ فَهِيَ لِرَجُلٍ أَجْرٌ وَهِيَ لِرَجُلٍ سَتْرٌ وَهِيَ عَلَى رَجُلٍ وِزْرٌ فَأَمَّا الَّذِي هِيَ لَهُ أَجْرٌ فَالَّذِي يَحْتَبِسُهَا فِي سَبِيلِ اللَّهِ فَيَتَّخِذُهَا لَهُ وَلاَ تُغَيِّبُ فِي بُطُونِهَا شَيْئًا إِلاَّ كُتِبَ لَهُ بِكُلِّ شَىْءٍ غَيَّبَتْ فِي بُطُونِهَا أَجْرٌ وَلَوْ عَرَضَتْ لَهُ مَرْجٌ ‏"‏ ‏.‏ وَسَاقَ الْحَدِيثَ ‏.‏