In the 'Tale of Kay Khosrow and the Cup of Jamshid' from Attar's Elahi Nameh, Kay Khosrow realizes that despite possessing the mythical Cup of Jamshid—which reveals all worldly secrets—he cannot perceive ultimate divine truth. The poem conveys that spiritual enlightenment cannot be achieved through external, worldly instruments of knowledge. Instead, it requires Fana (annihilation of the self). The verses emphasize that once the individual ego, body, and soul are completely erased, no separate 'self' remains to observe or be reflected in the material world, rendering artifacts like the Cup ultimately irrelevant to true spiritual union.