مَنْ رَأَى مِنْكُمْ مُنْكَرًا فَلْيُغَيِّرْهُ بِيَدِهِ، فَإِنْ لَمْ يَسْتَطِعْ فَبِلِسَانِهِ، فَإِنْ لَمْ يَسْتَطِعْ فَبِقَلْبِهِ، وَذَلِكَ أَضْعَفُ الْإِيمَانِ
Transliteration
Man ra'a minkum munkaran fa-l-yughayyirhu bi-yadih, fa-in lam yastati' fa-bi-lisanih, fa-in lam yastati' fa-bi-qalbih, wa dhalika ad'afu-l-iman.
Translation
Whoever sees a wrong, let him change it with his hand. If he cannot, then with his tongue. If he cannot, then with his heart, and that is the weakest of faith.
Narrated by Abu Sa'id al-Khudri·Sahih Muslim 49·Nawawi's Forty · #34
