The Fourth Book begins with an address to Husamu-`d-Din, and this is followed by the story of the lover and his mistress, already commenced in the third book. A certain lover had been separated from his mistress for the space of seven years, during which he never relaxed his efforts to find her. At last his constancy and perseverance were rewarded, in accordance with the promises The seeker shall find, and Whoso shall have wrought an atom`s weight of good shall behold it.