In classical Greece, different kinds of itinerant purifiers are well known mainly through hostile descriptions (Plato, Demosthenes) and sometimes also through some evidence from inside (Empedocles, Orphic gold tablets). However, both perspectives coincide in showing that such wandering “priests” aimed to construe a transportable sacred space, attached to specific people rather than to any specific location. Thus, sacred places could easily turn into metaphorical images for inner states. The main mechanisms of such construction are: creating conceptual boundaries which separate the initiate from the profane; depicting imaginary spaces of purity and impurity at both sides of the boundary; and imagining ways of spatial change from the impure to the pure side, be it as a gradual process (imagined as walking through a path) or as a sudden transportation (imagined as leaping or falling). Sacred space as a metaphor for inner religious experience gained enormous popularity from Plato onwards, and this kind of construction may have been the most immediate antecedent. This approach helps to explain several pieces of evidence of Greek itinerant religion, and, more generally, to understand how the possibility of internalizing sacred spaces may be exploited in specific situations.