أَخْبَرَنَا قُتَيْبَةُ، عَنْ مَالِكٍ، عَنْ سُمَىٍّ، عَنْ أَبِي صَالِحٍ، عَنْ أَبِي هُرَيْرَةَ، - رضى الله عنه - أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " إِذَا قَالَ الإِمَامُ { غَيْرِ الْمَغْضُوبِ عَلَيْهِمْ وَلاَ الضَّالِّينَ } فَقُولُوا آمِينَ فَإِنَّهُ مَنْ وَافَقَ قَوْلُهُ قَوْلَ الْمَلاَئِكَةِ غُفِرَ لَهُ مَا تَقَدَّمَ مِنْ ذَنْبِهِ " .
It was narrated that Abu Hurairah, may Allah be pleased with him, that: The Messenger of Allah (PBUH) said: "When the Imam says: Not (the way) of those who earned Your anger, nor of those who went astray, say: 'Amin,' for if a person's Amin coincides with the Amin of the angels, his previous sins will be forgiven.'" Translation Not Available
Book Ref: Sunan An Nisai Book 11 Hadith 929
Web Ref: Sunan An Nisai Vol 2 Book 11 Hadith 930