I saw that the Messenger of Allah ﷺ was twisting the forelock of a horse with his fingers and he was saying: (A great) benefit. i. e. reward (for rearing them for Jihad) and spoils of war, has been tied to the forelocks of horses until the Day of Judgment. (Using translation from Muslim 1872a)
رَأَيْتُ رَسُولَ اللهِ ﷺ يَفْتِلُ عُرْفَ فَرَسٍ بِأُصْبُعَيْهِ وَهُوَ يَقُولُ الْخَيْلُ مَعْقُودٌ بِنَوَاصِيهَا الْخَيْرُ الْأَجْرُ وَالْمَغْنَمُ إِلَى يَوْمِ الْقِيَامَةِ