"(The burden of) what is said by the two who vilify each other is upon the one who initiated it, as long as the one who was wronged does not transgress."  

أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ الْمُسْتَبَّانِ مَا قَالاَ فَعَلَى الْبَادِي مِنْهُمَا مَا لَمْ يَعْتَدِ الْمَظْلُومُ وَفِي الْبَابِ عَنْ سَعْدٍ وَابْنِ مَسْعُودٍ وَعَبْدِ اللَّهِ بْنِ مُغَفَّلٍ  

"Do not vilify the dead (and) by that harm the living."  

قَالَ رَسُولُ اللَّهِ ﷺ لاَ تَسُبُّوا الأَمْوَاتَ فَتُؤْذُوا الأَحْيَاءَ