Tafseer Ibn Kathir of AL KAHFI [99]

وَتَرَكْنَا بَعْضَهُمْ يَوْمَئِذٍ يَمُوجُ فِي بَعْضٍ وَنُفِخَ فِي الصُّورِ فَجَمَعْنَاهُمْ جَمْعًا

And We will leave them that day surging over each other, and [then] the Horn will be blown, and We will assemble them in [one] assembly.