AbstractThis paper seeks to shed light on the metaphorical discourse of the secretive minority religion of Yārsān. Metaphor is demonstrated as a central rhetorical device, applied as a linguistic apparatus that serves the ideology of concealment. To express heterodox concepts, Yārsān texts principally employ two rhetorical devices, metaphor and lexical substitution. The metaphorical models objectively conceptualize highly abstract religious notions and serve to obscure heretical concepts that strongly vary from established orthodox beliefs. As for lexical substitution, the most frequent metaphorical models are verbalized using foreign loanwords that are not common in Kurdish dialects. Together, these strategies construct a highly puzzling and mysterious discourse that is too difficult for outsiders to unravel. It can be argued that the metaphorical discourse of Yārsān functions as an anti-language that effectively challenges the limitations of expression imposed by the orthodox mainstream in the medieval era. Yārsān followers are able to express non-expressible ideas and disguise them within complicated imageries.