Sahih al-Bukhari 2438

Muhammad ibn Yusuf narrated to us: Sufyan narrated to us, from Rabi'a, from Yazid, the client of al-Munba'ith, from Zayd ibn Khalid (may Allah be pleased with him): A Bedouin asked the Prophet (peace and blessings be upon him) about found property. He said: ‘Announce it for a year. If someone comes and describes its container and tie, return it to him; otherwise, make use of it.’ The man asked him about a lost camel. The Prophet’s face changed, and he said: ‘What business have you with it? It has its water reserve and shoes; it reaches water and eats trees. Leave it until its owner finds it.’ He asked him about a lost sheep, and the Prophet said: ‘It is yours, your brother’s, or the wolf’s.’