Sahih Muslim , Book 37, Hadith 6611 (USC-MSA) ⓘ
Abu Huraira reported Allah's Messenger as saying: Allah is more pleased with the repentance of His servant when he turns penitently towards Him than one of you would be on finding the lost camel.
حَدَّثَنِي عَبْدُ اللَّهِ بْنُ مَسْلَمَةَ بْنِ قَعْنَبٍ الْقَعْنَبِيُّ، حَدَّثَنَا الْمُغِيرَةُ، - يَعْنِي ابْنَ عَبْدِ الرَّحْمَنِ الْحِزَامِيَّ - عَنْ أَبِي الزِّنَادِ، عَنِ الأَعْرَجِ، عَنْ أَبِي هُرَيْرَةَ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " لَلَّهُ أَشَدُّ فَرَحًا بِتَوْبَةِ أَحَدِكُمْ مِنْ أَحَدِكُمْ بِضَالَّتِهِ إِذَا وَجَدَهَا " .
also referenced under: Book 50, Hadith 2 (In-Book) & Hadith 2675 (Reference)