Misbelievers are unjust, and shall not be allowed to understand, or be guided.
But God is merciful.
Story of Moses and his servant in search of al-K͟hiẓr.
They lose their fish at the confluence of the two seas.
They meet a strange prophet, who bids Moses not question anything he may do.
He scuttles a ship, kills a boy, and builds up a tottering wall.
Moses desires an explanation, which the stranger gives, and leaves him.
Story of Ẕū ʾl-Qarnain.
He travels to the ocean of the setting sun.
Builds a rampart to keep in Gog and Magog.