Sahih Muslim 1068aBook 12, Hadith 207
حَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا عَلِيُّ بْنُ مُسْهِرٍ، عَنِ الشَّيْبَانِيِّ، عَنْ يُسَيْرِ بْنِ، عَمْرٍو قَالَ سَأَلْتُ سَهْلَ بْنَ حُنَيْفٍ هَلْ سَمِعْتَ النَّبِيَّ صلى الله عليه وسلم يَذْكُرُ الْخَوَارِجَ فَقَالَ سَمِعْتُهُ - وَأَشَارَ بِيَدِهِ نَحْوَ الْمَشْرِقِ " قَوْمٌ يَقْرَءُونَ الْقُرْآنَ بِأَلْسِنَتِهِمْ لاَ يَعْدُو تَرَاقِيَهُمْ يَمْرُقُونَ مِنَ الدِّينِ كَمَا يَمْرُقُ السَّهْمُ مِنَ الرَّمِيَّةِ " .
Did you hear the Messenger of Allah (ﷺ) making a mention of the Khawarij? He said: I heard him say (and he pointed with his hand towards the east) that these would be a people who would recite the Qur'an with their tongues and it would not go beyond their collar bones. They would pass clean through their religion just as the arrow passes through the prey.