Sahih al-Bukhari — Fighting for the Cause of Allah (Jihaad) — Hadith No: 2852
Translation
Narrated `Urwa Al-Bariqi:The Prophet (ﷺ) said, "Good will remain (as a permanent quality) in the foreheads of horses (for Jihad) till the Day of Resurrection, for they bring about either a reward (in the Hereafter) or (war) booty (in this world)