regret and remorse in the afterlife

يَوْمَئِذٍ يَوَدُّ ٱلَّذِينَ كَفَرُوا۟ وَعَصَوُا۟ ٱلرَّسُولَ لَوْ تُسَوَّىٰ بِهِمُ ٱلْأَرْضُ وَلَا يَكْتُمُونَ ٱللَّهَ حَدِيثًا

That Day, those who disbelieved and disobeyed the Messenger will wish they could be covered by the earth. And they will not conceal from Allāh a [single] statement.

قَالُوا۟ لَمْ نَكُ مِنَ ٱلْمُصَلِّينَ

They will say, "We were not of those who prayed,