Sayyiduna Ali bin Abi Talib (may Allah be pleased with him) reports that the Prophet (peace and blessings be upon him) said: "Indeed, Allah Almighty loves the believing servant who is tried (that is, who falls into sin) and who repents abundantly."
Abdullah and Abu Ya'la recorded it; its chain contains a narrator whom I do not know.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب التوبة / 17529