صحيح البخاري

Narrated Ibn `Umar:

That he was in the company of the Prophet (ﷺ) on a journey, riding a troublesome camel belonging to `Umar. The camel used to go ahead of the Prophet, so Ibn `Umar's father would say, "O `Abdullah! No one should go ahead of the Prophet." The Prophet (ﷺ) said to him, "Sell it to me." `Umar said to the Prophet "It is for you." So, he bought it and said, "O `Abdullah! It is for you, and you can do with it what you like."