Inevitability of Judgment

إِن كَانَتْ إِلَّا صَيْحَةً وَٰحِدَةً فَإِذَا هُمْ خَـٰمِدُونَ

It was not but one shout, and immediately they were extinguished.

ثُمَّ كَلَّا سَيَعْلَمُونَ

Then, no! They are going to know.