﴿ فَلَعَلَّكَ بَٰخِعٌۭ نَّفْسَكَ عَلَىٰٓ ءَاثَٰرِهِمْ إِن لَّمْ يُؤْمِنُوا۟ بِهَٰذَا ٱلْحَدِيثِ أَسَفًا ﴾

“But wouldst thou, perhaps, torment thyself to death with grief over them if they are not willing to believe in this message?”

Yet it may be that you will consume destroy yourself in their wake — following your being with them that is after they have left you — if they should not believe in this discourse in this Qur’ān out of grief out of rage and anguish on your part because of your eagerness that they believe asafan ‘out of grief’ is in the accusative because it functions as an object denoting reason.