Chapter 23: The Book on Jihad
Narrated Anas bin Malik: "There was a cause of fright in Al-Madinah. So the Messenger of Allah (ﷺ) borrowed a horse of ours called Mandub. He said: 'I have not seen anything to be frightened of, and we found him to be (quick) like the sea.'"[Abu 'Eisa said: ] This Hadith is Hasan Sahih.
Jami at-Tirmidhi 1686