وَعَنْ أَبِي جُحَيْفَةَ رضى الله عنه
قَالَ: «رَأَيْتُ بِلَالاً يُؤَذِّنُ وَأَتَتَبَّعُ فَاهُ، هَاهُنَا وَهَاهُنَا، وَإِصْبَعَاهُ فِي أُذُنَيْهِ»
I saw Bilal calling for prayer and I would follow (looking at) his mouth (as he turned it) this (right) side and that (left) side with his fingers in his ears.