This chapter, by Kath Stevenson, explains that traditions of Christian knowledge are an abiding preoccupation for William Langland in Piers Plowman, with Langland exploring fundamental questions about the pre-eminence or otherwise of abstract learning, textually mediated and transmitted (‘clergie’), over experiential knowledge (‘kynde knowynge’) and about the role of learning in Christian salvation. What good is knowledge? In an age of abstruse academic discourse, in which Langland himself was deeply versed, Langland’s protagonist Will searches urgently for the knowledge that is truly valuable, that is, the knowledge that will enable him to save his soul. Stevenson locates Langland’s ambivalence concerning the efficacy of textually mediated learning within the wider contexts of vernacular theology in the late fourteenth and fifteenth centuries and in particular shows Langland’s treatment of the Passion in the central passus of his poem to be informed by the developing traditions of affective piety. For Langland the Passion can function as a site in which textual and experiential knowledge are united, with abstract intellectual knowledge becoming transfigured as it is fused with ‘kynde knowynge’