One hypothesis dates the identification with healing to before the composition of the Gathic "airyaman ishyo". Here, (following a well established meaning) "member of (the) community," is interpreted to signify a member "of the fellowship of priests ("sodalis")." Accordingly, Airyaman came to be understood as the divinity of healing (and the prayer came to be considered a charm against sickness) because in antiquity priests were repositories of medicinal knowledge and "the healer among healers was he who healed by the holy WORD."