Surah Al-Anbya — Ayah 40 (21:40)
بَلۡ تَأۡتِيهِم بَغۡتَةٗ فَتَبۡهَتُهُمۡ فَلَا يَسۡتَطِيعُونَ رَدَّهَا وَلَا هُمۡ يُنظَرُونَ ٤٠
English translation (Saheeh International)
Rather, it will come to them unexpectedly and bewilder them, and they will not be able to repel it, nor will they be reprieved.
Brief commentary
This fire that they shall be punished with will come upon them suddenly, without them anticipating it. They shall not be able to repel it, nor shall they be given respite to repent and consequently be shown mercy.