Imam Husayn (pbuh)
إيَّاكَ وَ مَا تَعْتَذِرُ مِنْهُ فَإِنَّ اَلْمُؤْمِنَ لاَ يُسِيءُ وَ لاَ يَعْتَذِرُ وَ اَلْمُنَافِقُ كُلَّ يَوْمٍ يُسِيءُ وَ يَعْتَذِرُ
Keep away from doing that which you must excuse yourself for, for verily the believer neither commits a wrong nor makes excuses for himself, whereas the hypocrite commits wrongs and makes excuses for them everyday.
Tuhaf al-’Uqul, no. 248
