For the Day of Sorting out.
Cf. 37:21 and n. 4047; also 44:40, and (n.
That will be the Day of Judgment or Day of Decision.
Good will then be completely separated from Evil. And
the men who rejected Truth and flourished on Falsehood
will find that in the world of Realities they will be
absolutely nowhere. Hence the refrain of this Surah.
“Ah woe, that Day, to the Rejecters of Truth!”
it sounds like a dirge on Sin
Yusuf Ali, Abdullah. Translation and Commentary of the Quran. (surah 77 verse 13) Quran Arabic with English Translation & Commentary (Tafsir) by Abdullah Yusuf Ali, Free Download (quran4u.com)