´It was narrated from Abu Hurairah that the Messenger of Allah (ﷺ) said:` “When the reciter says Amin, then say Amin, for the angels say Amin, and if a person’s Amin coincides with the Amin of the angels, his previous sins will be forgiven.”
Hadith ReferenceSunan Ibn Majah / Establishing the Prayer and the Sunnah Regarding Them / Hadith: 851
Hadith Gradingالألبانی:صحيح | زبیر علی زئی:صحيح بخاري