Cryptic inscriptions in architectural spaces, as informal writing practices, have often been pushed to the margins of text-centered studies and treated merely as individual acts or damage to historical monuments. Yet these inscriptions can carry semantic, historical, and discursive layers that emerge in relation to prior texts and the spatial context. The central problem of this research is how to read and interpret the cryptic inscriptions behind the entrance door of Bayazid Bastami Mosque in Bastam within Gerard Genette’s framework of transtextuality. The study aims to analyze these inscriptions as multilayered texts and to reveal the network of intertextual, paratextual, metatextual, hypertextual, and architextual relations they establish with mystical traditions, religious texts, and the spatial-architectural structure of the mosque. Accordingly, the research question is: How can the cryptic inscriptions in the Bayazid Bastami Mosque be analyzed as multilayered texts within a network of transtextual relations? Methodologically, the study is qualitative and descriptive-comparative, grounded in Genette’s theory of transtextuality. Data collection combined fieldwork and library research: the inscriptions were documented through direct observation and high-resolution digital photography, then analyzed comparatively and hermeneutically using theoretical sources, mystical writings, historical accounts, and studies of vernacular inscriptions.

Findings show that the cryptic inscriptions under study go beyond individual pilgrim experiences and acquire meaning within a network of texts, symbols, and mystical-historical discourses. Analysis through Genette’s five categories of transtextuality reveals dynamic relations with mystical texts, Sufi beliefs, and the spatial significance of the mosque’s entrance, generating meaning across time and place. The study concludes that texts inscribed in sacred spaces, even in the form of cryptic graffiti, carry complex linguistic, historical, and mystical layers.