The present study aims to explore the ontological foundations of mirror work in sacred spaces by examining the relationship between the holy architecture of Hazrat Masoumeh shrine and the concept of Wilayat in Shiite wisdom based on the theory of unity of being and the concept of manifestation. Mirror work in Islamic architecture is not merely decorative but the physical embodiment of profound mystical concepts that guide audiences from the multiplicity of the material world to the unity of the spiritual realm. This qualitative research uses a descriptive analytical method based on the phenomenology of Henry Corbin and the concept of unveiling the hidden. By utilizing the mystical allegory of the candle and mirror found in the views of Islamic philosophers like Seyyed Haydar Amuli, the luminous and physical structure of the shrine space was analyzed. In this model, the holy tomb is considered the candle and source of light while the mirror surfaces are analyzed as manifestations of this light. The research findings indicate a meaningful distinction between two types of mirror work in the shrine architecture. The small broken mirrors in the ceiling vaults symbolize the world of multiplicity and the limited capacity of beings in reflecting divine light. Conversely, the large flat mirrors installed at the entrance of the tomb reflect the light without any distortion. The conclusion suggests that these large flat mirrors are the physical embodiment of the Perfect Man and the Wilayat of the holy Imams. The Imams act as a polished mirror representing the complete manifestation of God reflecting divine light perfectly. Consequently, the mirror work of Hazrat Masoumeh shrine creates an intuitive journey from multiplicity to unity for pilgrims translating the geometry of Shiite beliefs into form and space.