The Messenger of Allah ﷺ said, "Allah rejoices more at the repentance of His servant than any one of you who finds his camel after having lost it in a barren land."
قال رسول الله ﷺ: الله أفرح بتوبة عبده من أحدكم سقط على بعيره، وقد أضله في أرض فلاة.
Bukhari narrated it in the Book of Supplications (6309), and Muslim narrated it in the Book of Repentance (2747), both from the hadith of Hudbah bin Khalid, also called Hadaab, from Hammam bin Yahya, who said, Qatada narrated to us, from Anas, and he mentioned the same. The wording given is Bukhari's, while Muslim's wording is, "Allah is more joyful at the repentance of His servant than one of you would be upon waking to find his camel, which he had lost in a barren land."