إِنَّآ أَنذَرْنَٰكُمْ عَذَابًا قَرِيبًا يَوْمَ يَنظُرُ ٱلْمَرْءُ مَا قَدَّمَتْ يَدَاهُ وَيَقُولُ ٱلْكَافِرُ يَٰلَيْتَنِى كُنتُ تُرَٰبًۢا ٤٠
Innaa andharnaakum `adhaaban qareebay yawma yanzurul-mar'u maa qaddamat yadaahu wayaqoolul-kaafiru yaalaytanee kuntu turaabaa
Indeed, We have warned you of an impending punishment on the Day when a man will observe what his hands have put forth and the disbeliever will say, "Oh, I wish that I were dust!"
- i.e., the deeds he did in this world, which await him in the Hereafter.