regret in the afterlife

قَالُوا۟ رَبَّنَا مَن قَدَّمَ لَنَا هَـٰذَا فَزِدْهُ عَذَابًا ضِعْفًا فِى ٱلنَّارِ

They will say, "Our Lord, whoever brought this upon us - increase for him double punishment in the Fire."

أَن تَقُولَ نَفْسٌ يَـٰحَسْرَتَىٰ عَلَىٰ مَا فَرَّطتُ فِى جَنۢبِ ٱللَّهِ وَإِن كُنتُ لَمِنَ ٱلسَّـٰخِرِينَ

Lest a soul should say, "Oh, [how great is] my regret over what I neglected in regard to Allāh and that I was among the mockers."

حَتَّىٰٓ أَتَىٰنَا ٱلْيَقِينُ

Until there came to us the certainty [i.e., death]."