Sahih Muslim 2499
Abu Musa reported that Messenger of Allah ﷺ said: I recognise the voice of the Ash'arites while they recite the Qur'an as they arrive during the night and I also recognise their station from the recital of the Qur'an during the night time, although I have not seen their encampments as they encamp during the day time. And there is a person amongst them, Hakim;
when he encounters the horsemen or the enemies he says to them: My friends command you to wait for them.
حَدَّثَنَا أَبُو كُرَيْبٍ، مُحَمَّدُ بْنُ الْعَلاَءِ حَدَّثَنَا أَبُو أُسَامَةَ، حَدَّثَنَا بُرَيْدٌ، عَنْ أَبِي بُرْدَةَ، عَنْ أَبِي مُوسَى، قَالَ قَالَ رَسُولُ اللَّهِ ﷺ " إِنِّي لأَعْرِفُ أَصْوَاتَ رُفْقَةِ الأَشْعَرِيِّينَ بِالْقُرْآنِ حِينَ يَدْخُلُونَ بِاللَّيْلِ وَأَعْرِفُ مَنَازِلَهُمْ مِنْ أَصْوَاتِهِمْ بِالْقُرْآنِ بِاللَّيْلِ وَإِنْ كُنْتُ لَمْ أَرَ مَنَازِلَهُمْ حِينَ نَزَلُوا بِالنَّهَارِ وَمِنْهُمْ حَكِيمٌ إِذَا لَقِيَ الْخَيْلَ - أَوْ قَالَ الْعَدُوَّ - قَالَ لَهُمْ إِنَّ أَصْحَابِي يَأْمُرُونَكُمْ أَنْ تَنْظُرُوهُمْ " .