Ash-Shu'araa • BN-TAFSEER-IBN-E-KASEER
﴿ لَا يُؤْمِنُونَ بِهِۦ حَتَّىٰ يَرَوُا۟ ٱلْعَذَابَ ٱلْأَلِيمَ ﴾
“they will not believe in it till they behold the grievous suffering”
Please check ayah 26:209 for complete tafsir.