Bulugh al-Maram, Book 3, Hadith 621 (English) ⓘ
A’ishah (RAA) narrated that the Messenger of Allah said: “Do not speak badly of the dead, they have already seen the result of (the deeds) that they sent on before them.” Related by Al·Bukhari.
وَعَنْ عَائِشَةَ رَضِيَ اَللَّهُ عَنْهَا قَالَتْ: قَالَ رَسُولُ اَللَّهِ - صلى الله عليه وسلم -{ لَا تَسُبُّوا الْأَمْوَاتَ, فَإِنَّهُمْ قَدْ أَفْضَوْا إِلَى مَا قَدَّمُوا } رَوَاهُ اَلْبُخَارِيّ ُ 1. 1 - صحيح. رواه البخاري ( 1393 ).
also referenced under: Book 3, Hadith 65 (In-Book)