the Prophet said: “No group gather in a sitting in which they do not remember Allah, nor sent Salat upon their Prophet, except it will be a source of remorse for them. If He wills, He will punish them, and if He wills, He will forgive them.”  

عَنِ النَّبِيِّ ﷺ قَالَ مَا جَلَسَ قَوْمٌ مَجْلِسًا لَمْ يَذْكُرُوا اللَّهَ فِيهِ وَلَمْ يُصَلُّوا عَلَى نَبِيِّهِمْ إِلاَّ كَانَ عَلَيْهِمْ تِرَةً فَإِنْ شَاءَ عَذَّبَهُمْ وَإِنْ شَاءَ غَفَرَ لَهُمْ