Surah Fussilat (فصلت) Ayah 13 - Tafsir

فَإِنْ أَعْرَضُوا۟ فَقُلْ أَنذَرْتُكُمْ صَٰعِقَةًۭ مِّثْلَ صَٰعِقَةِ عَادٍۢ وَثَمُودَ

"But if they turn away, then say, "I have warned you of a thunderbolt like the thunderbolt [that struck] 'Aad and Thamud."