(35) باب فَضْلِ التَّأْمِينِ
It was narrated from Abu Hurairah that:
The Messenger of Allah (ﷺ) said: "If any one of you says: 'Amin' and the angels in Heaven say Amin, and the one coincides with the other, his previous sins will be forgiven."
Reference: Sunan an-Nasa'i 930
In-book reference: Book 11, Hadith 55
English translation: Vol. 2, Book 11, Hadith 931