Sahih al-Bukhari 2437

Sulayman ibn Harb narrated to us: Shu'ba narrated to us, from Salama ibn Kuhayl, who said: I heard Suwayd ibn Ghafala say: I was with Salman ibn Rabi'a and Zayd ibn Suhan on a military expedition when I found a whip. One of them told me, ‘Drop it.’ I said, ‘No. If I find its owner, I will return it; otherwise, I will make use of it.’ When we returned, we performed the pilgrimage, and I passed through Medina and asked Ubayy ibn Ka'b (may Allah be pleased with him). He said: ‘In the time of the Prophet (peace and blessings be upon him), I found a purse containing one hundred dinars and brought it to him. He said, “Announce it for a year.” I announced it for a year, then came back. He said, “Announce it for a year.” I announced it for a year, then came back. He said, “Announce it for a year.” I announced it for a year, then came to him a fourth time. He said, “Remember its amount, its tie, and its container. If its owner comes, return it; otherwise, make use of it.”’