Al-Harith bin Suwaid said:
" 'Abdullah [bin Mas'ud] narrated two Ahadith to us, one of them from himself and the other from the Prophet (s.a.w). 'Abdullah said: 'The believer sees his sins as if he was at the base of a mountain, fearing that it was about to fall upon him. The wicked person sees his sins as if (they are) flies are hitting his nose" he said: "Like this" - motioning with his hand - "to get them to fly away."
حَدَّثَنَا هَنَّادٌ، أَخْبَرَنَا أَبُو مُعَاوِيَةَ، عَنِ الأَعْمَشِ، عَنْ عُمَارَةَ بْنِ عُمَيْرٍ، عَنِ الْحَارِثِ بْنِ سُوَيْدٍ، حَدَّثَنَا عَبْدُ اللَّهِ بْنُ مَسْعُودٍ، بِحَدِيثَيْنِ أَحَدُهُمَا عَنْ نَفْسِهِ، وَالآخَرُ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ عَبْدُ اللَّهِ إِنَّ الْمُؤْمِنَ يَرَى ذُنُوبَهُ كَأَنَّهُ فِي أَصْلِ جَبَلٍ يَخَافُ أَنْ يَقَعَ عَلَيْهِ وَإِنَّ الْفَاجِرَ يَرَى ذُنُوبَهُ كَذُبَابٍ وَقَعَ عَلَى أَنْفِهِ قَالَ بِهِ هَكَذَا فَطَارَ ‏.‏
GradeSahih (Darussalam)
English reference : Vol. 4, Book 11, Hadith 2497
Arabic reference : Book 37, Hadith 2685