Sunan Ibn Majah, Book 20, Hadith 2641 (In-Book) ⓘ
It was narrated from Abu Hurairah that the Messenger of Allah said: “Whoever covers (the sin of) a Muslim, Allah will cover him (his sin) in this world and in the Hereafter.”
حَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا أَبُو مُعَاوِيَةَ، عَنِ الأَعْمَشِ، عَنْ أَبِي صَالِحٍ، عَنْ أَبِي هُرَيْرَةَ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " مَنْ سَتَرَ مُسْلِمًا سَتَرَهُ اللَّهُ فِي الدُّنْيَا وَالآخِرَةِ " .
also referenced under: Hadith 2544 (Reference) & Volume 3, Book 20, Hadith 2544 (DarusSalam)