“and whatever is hidden in the hearts is brought to light * surely their Lord is, on that Day, fully aware of them.”

“Whatever is hidden in the hearts is brought to light.” That is, [what they contain and] whatever was concealed within hearts—the latent good and evil—will emerge and become evident. Thus every secret becomes public, all that was inward becomes manifest, and the fruits of people’s deeds appear upon their faces.

“Surely their Lord is, on that Day, fully aware of them.” That is, He is fully apprised of all their deeds—outward and inward, hidden and manifest—and will recompense them for them. He specifically mentions His awareness of them (1) on that Day, even though He is aware of them at all times, because what is intended here is the recompense for deeds (2) arising from Allah’s knowledge and full awareness.

Commentary on Surah al-Qāriʿah

[It is] Meccan