﴿ وَٱلَّذِينَ سَعَوْ فِىٓ ءَايَٰتِنَا مُعَٰجِزِينَ أُو۟لَٰٓئِكَ لَهُمْ عَذَابٌۭ مِّن رِّجْزٍ أَلِيمٌۭ ﴾

“whereas for those who strive against Our messages, seeking to defeat their purpose, there is grievous suffering in store as an outcome of [their] vileness.”

The addressees of the Quran were not disbelievers in the Day of Judgement. It was just that they did not believe that Judgement Day would bring them humiliation and punishment. The world they lived in appeared safe to them and they could not, therefore, understand how they would be in jeopardy on reaching the world Hereafter. This truth about life and the Universe is found in all divine scriptures. It is the Quran’s mission to reveal this reality in its pure and unadulterated form. Now, those who take a stand in opposition to this mission are indulging in the most improper bravado. Before God, they will be treated as deserving of the severest punishment.