﴿ فَلَمَّا بَلَغَا مَجْمَعَ بَيْنِهِمَا نَسِيَا حُوتَهُمَا فَٱتَّخَذَ سَبِيلَهُۥ فِى ٱلْبَحْرِ سَرَبًۭا ﴾

“But when they reached the junction between the two [seas], they forgot all about their fish, and it took its way into the sea and disappeared from sight.”

So when they reached a juncture between the two, in the all-comprehensive present form, they forgot their fish, which is the fish that swallowed Dhū'l-Nūn, may peace be upon him, as a type and not as that individual [fish], because their breakfast was before their arrival at this form externally from that fish which he had been commanded to take as a provision for the journey at the moment of resolve; and so it made its way, into the sea of the body alive as it had been at the first instance, by burrowing, a wide tunnel, as is related. Its [tunnelled] path to the sea remained open and was not covered over by the [waters of the] sea.