Mishkat al-Masabih #3755

Buraida told that while God’s Messenger was walking a man who had an ass came to him and, moving to the back of the animal, invited him to mount, but he said, “No; you have more right to ride in front on your animal unless you grant that right to me." The man replied that he did, and so he mounted. Tirmidhi and Abu Dawud transmitted it.