Has the story reached you of the hosts, Of Fir`awn and Thamud?
meaning, has the news reached you of what Allah caused to befall them of torment, and that He sent down upon them the punishment that no one was able to ward off from them
This is the affirmation of His statement,
إِنَّ بَطْشَ رَبِّكَ لَشَدِيدٌ
(Verily, the punishment of your Lord is severe and painful). meaning, when He seizes the wrongdoer, He seizes him with a severe and painful punishment. It is the seizing punishment of One Most Mighty, and Most Powerful.
Then Allah says,
بَلِ الَّذِينَ كَفَرُوا فِي تَكْذِيبٍ