Al-Nawwas bin Sam’an, radiyallahu ’anhu, reported that the Prophet, sallallahu ’alayhi wasallam, said: \”Righteousness is good character, and sin is that which wavers in your heart and which you do not want people to know about.\” [Muslim] According to Wabisah bin Ma’bad, radiyallahu ’anhu, who said: I came to the Messenger of Allah, sallallahu ’alayhi wasallam, and he said: \”You have come to ask about righteousness ?\” \” Yes,\” I answered. He said: \”Consult your heart. Righteousness is that about which the soul feels tranquil and the heart feels tranquil, and sin is what creates restlessness in the soul and moves to and fro in the breast, even though people give you their opinion (in your favour) and continue to do so.\”
