سُبْحَانَ ٱللَّٰهِ
Holy Qur'an
Al-Qur'an
Kids Qur'an
I.e., the Day of Resurrection - thus reverting to the theme enunciated in verses {62-66} above.
This repetition of God's "question", already mentioned in verse {62} above, is meant to stress the utter inability of the sinners concerned to justify their erstwhile attitude rationally; hence my interpolation at the beginning of the next verse.
Cf. xxviii. 62 above. The reminiscence of the words closes and rounds off the argument of this Section.