'Urwat al-Bariqi reported Allah's Messenger (ﷺ) having said this:Good is tied to the forelock of the horses. It Was said to him: Messenger of Allah, why is it so? He (the Prophet said): For reward and booty until the Day of Judgment.
وَحَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا ابْنُ فُضَيْلٍ، وَابْنُ، إِدْرِيسَ عَنْ حُصَيْنٍ، عَنِ الشَّعْبِيِّ، عَنْ عُرْوَةَ الْبَارِقِيِّ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " الْخَيْرُ مَعْقُوصٌ بِنَوَاصِي الْخَيْلِ " . قَالَ فَقِيلَ لَهُ يَا رَسُولَ اللَّهِ بِمَ ذَاكَ قَالَ " الأَجْرُ وَالْمَغْنَمُ إِلَى يَوْمِ الْقِيَامَةِ " .
Muslim
The Book on Government • Hadith 146