Nawwis b. Sim'in reported: I stayed with Messenger of Allah ﷺ for one year. What obstructed me to migrate was (nothing) but (persistent) inquiries from him (about Islam). (It was a common observation) that when anyone of us migrated (to Medina) he ceased to ask (too many questions) from Messenger of Allah ﷺ. So I asked him about virtue and vice. Thereupon Messenger of Allah ﷺ said: Virtue is a kind disposition and vice is what rankles in your mind and that you disapprove of its being known to the people.

حَدَّثَنِي هَارُونُ بْنُ سَعِيدٍ الأَيْلِيُّ، حَدَّثَنَا عَبْدُ اللَّهِ بْنُ وَهْبٍ، حَدَّثَنِي مُعَاوِيَةُ، - يَعْنِي ابْنَ صَالِحٍ - عَنْ عَبْدِ الرَّحْمَنِ بْنِ جُبَيْرِ بْنِ نُفَيْرٍ، عَنْ أَبِيهِ، عَنْ نَوَّاسِ بْنِ سِمْعَانَ، قَالَ أَقَمْتُ مَعَ رَسُولِ اللَّهِ ﷺ بِالْمَدِينَةِ سَنَةً مَا يَمْنَعُنِي مِنَ الْهِجْرَةِ إِلاَّ الْمَسْأَلَةُ كَانَ أَحَدُنَا إِذَا هَاجَرَ لَمْ يَسْأَلْ رَسُولَ اللَّهِ ﷺ عَنْ شَىْءٍ - قَالَ - فَسَأَلْتُهُ عَنِ الْبِرِّ وَالإِثْمِ فَقَالَ رَسُولُ اللَّهِ ﷺ " الْبِرُّ حُسْنُ الْخُلُقِ وَالإِثْمُ مَا حَاكَ فِي نَفْسِكَ وَكَرِهْتَ أَنْ يَطَّلِعَ عَلَيْهِ النَّاسُ " .