Surah Taha — Ayah 78 (20:78)
فَأَتۡبَعَهُمۡ فِرۡعَوۡنُ بِجُنُودِهِۦ فَغَشِيَهُم مِّنَ ٱلۡيَمِّ مَا غَشِيَهُمۡ ٧٨
English translation (Saheeh International)
So Pharaoh pursued them with his soldiers, and there covered them from the sea that which covered them,1
- - i.e., not only the water but that which only Allāh knows - terror, pain, regret, etc.
Brief commentary
Then Pharoah, accompanied by his armies, followed them. Then he and his armies were engulfed by part of the sea, the reality of which only Allah knows. They all drowned and perished, whilst Moses and those with him were saved.