وَعَنْ عَبْدِ اللَّهِ بْنِ مَسْعُودٍ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «سِبَابُ الْمُسْلِمِ فُسُوقٌ وَقِتَالُهُ كُفْرٌ» . مُتَّفَقٌ عَلَيْهِ
Abdullah bin Mas'ud (may Allah be pleased with him) reports that the Messenger of Allah (peace and blessings be upon him) said: "Abusing a Muslim is wickedness and fighting with him is disbelief." Agreed upon.