Standard typologies of religion tend to classify Old Norse religion as archaic or otherwise primitive, partly based on a supposed focus on praxis to the exclusion of theology. Taking that premise as a point of departure, this paper will explore what might be called the epistemology of Old Norse religion. Is Þórr a god of fertility because he controls the rain? Was the mead of poetry more than a metaphor to the poets who drank it? How far and how consistently are the mechanics of divine intervention conceptualized? Runic inscriptions directed at the god Þórr are used as a case study, in particular the Þórr vígi stones (DR 209, DR 220, DR 110, Vg 150) and the Canterbury Charm (DR 419). Through this investigation, I hope to discuss tendencies in Old Norse thought more broadly and to throw new light on the intellectual engagement of worshippers with their traditions.