Sayyiduna Abu Umamah (may Allah be pleased with him) narrates that a man asked the Prophet Muhammad (peace and blessings be upon him), "What is sin?" He (peace be upon him) replied: "Leave that which causes uneasiness in your chest." The man asked, "What is faith?" He (peace be upon him) replied: "When your sin displeases you and your good deed pleases you, then you are a believer."