Sahih al-Bukhari 2115

Al-Humaydi also said: Sufyan narrated to us: Amr narrated to us, from Ibn Umar, may Allah be pleased with them both, who said: “We were with the Prophet, peace and blessings be upon him, on a journey. I was riding a difficult young camel belonging to Umar. It would overpower me and go ahead of the group, so Umar would scold it and bring it back. Then it would go ahead again, and Umar would scold it and bring it back. The Prophet told Umar to sell it to him. Umar said that it was his, O Messenger of Allah. The Prophet again told him to sell it. So Umar sold it to the Messenger of Allah. The Prophet then said to me, Abdullah ibn Umar, it is yours. Do with it as you wish.”