"So observe how was the end of those before," meaning their end was that Allah destroyed them, then consigned them to the Fire.
Surah Ar-Rum, verses 43-47.
﴿فَانْظُر كَيْفَ كَانَ عَاقِبَةُ الَّذِينَ مِنْ قبل﴾ كَانَ عاقبتهم أَن دمر الله عَلَيْهِم ثمَّ صيرهم إِلَى النَّار.
سُورَة الرّوم من (آيَة ٤٣ آيَة ٤٧).
