Sahih Muslim 6006

Anas b. Malik reported that Allah's Messenger (ﷺ) was the sublimest among people (in character) and the most generous amongst them and he was the bravest of men. One night the people of Medina felt disturbed and set forth in the direction of a sound when Allah's Messenger (ﷺ) met them on his way back as he had gone towards that sound ahead of them. He was on the horse of Abu Talha which had no saddle over it, and a sword was slung round his neck, and he was saying:There was nothing to be afraid of, and he also said: We found it (this horse) like a torrent of water (indicating its swift-footedness), whereas the horse had been slow before that time