Surah Al-Qamar 54:18

كَذَّبَتْ عَادٌ فَكَيْفَ كَانَ عَذَابِى وَنُذُرِ

ʿAad denied; and how [severe] were My punishment and warning.

Translation: Saheeh International

Tafsir

‘Ād denied their prophet Hūd and so they were chastised. How then were My chastisement and My warnings? how then was My warning them of the chastisement before it was sent down? In other words it was justified and He explains this chastisement by saying

Excerpt from Tafsir al-Jalalayn, commentary on 54:18, via Quran.com. The reader has the full commentary and 9 more tafsirs.