عَنِ الْمُغِيرَةِ بْنِ شُعْبَةَ رَضِيَ اللَّهُ عَنْهُ قَالَ قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ لَا تَسُبُّوا الْأَمْوَاتَ فَتُؤْذُوا الْأَحْيَاءَ
It is narrated from Sayyiduna Mughirah bin Shu’bah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: Do not speak ill of the dead, for by doing so you will cause distress to the living.