فَلَمَّا بَلَغَا مَجْمَعَ بَيْنِهِمَا نَسِيَا حُوتَهُمَا فَاتَّخَذَ سَبِيلَهُ فِي الْبَحْرِ سَرَبًا (61)
(18:61) And it so happened that when they reached the confluence, they became neglectful of their fish and it burrowed its way to the river as through a tunnel.