Saying Amin aloud
حَدَّثَنَا مُحَمَّدُ بْنُ بَشَّارٍ، حَدَّثَنَا صَفْوَانُ بْنُ عِيسَى، حَدَّثَنَا بِشْرُ بْنُ رَافِعٍ، عَنْ أَبِي عَبْدِ اللَّهِ ابْنِ عَمِّ أَبِي هُرَيْرَةَ، عَنْ أَبِي هُرَيْرَةَ، قَالَ تَرَكَ النَّاسُ التَّأْمِينَ وَكَانَ رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ إِذَا قَالَ " {غَيْرِ الْمَغْضُوبِ عَلَيْهِمْ وَلاَ الضَّالِّينَ} " . قَالَ " آمِينَ " . حَتَّى يَسْمَعَهَا أَهْلُ الصَّفِّ الأَوَّلِ فَيَرْتَجُّ بِهَا الْمَسْجِدُ .
It was narrated that Abu Hurairah said: “The people stopped saying Amin, but when the Messenger of Allah (ﷺ) said ‘Not (the way) of those who earned Your Anger, nor of those who went astray’[1:7] he would say Amin, until the people in the first row could hear it, and the mosque would shake with it.