It might appear straightforward, on a first reading, that Dante’s Purgatory represents a penitential journey guided by Christian ethics to God. For most of the poem’s history, indeed, Purgatory has been read broadly in this way. In the second half of the twentieth century, however, a parallel interpretation emerged. Influenced by Dante’s dualistic theory of man’s two ethical goals (one temporal and one eternal), many scholars have argued that Purgatory represents a secular journey guided by philosophical principles to a temporal happiness. This article presents three major counterarguments to the secular reading of Purgatory, a reading proposed most powerfully in recent scholarship by John A. Scott’s monograph Dante’s Political Purgatory. First, it proposes a new way to read the poem as informed by Dante’s dualistic theory which does not entail a forced reading of Purgatory in overly political terms. Secondly, it demonstrates how Dante forged his vision of Purgatory through two areas of distinctively Christian theory and practice which had risen to particular prominence in the thirteenth century: the newly crystallised doctrine of Purgatory and the tradition of the seven capital vices (or deadly sins) in penitential ethics. Thirdly, it argues that the region embodies an explicit re-orientation from natural to supernatural ethics, from pagan to Christian exempla, and from this world to the heavenly city. Where Scott has argued for a ‘political Purgatory’, an ethical journey guided by ‘justice and the teachings of philosophy’ towards a secular goal, this article presents afresh, therefore, a ‘theological Purgatory’, a moral pilgrimage guided by distinctively Christian ethics towards God and the beatitudo vitae aeternae.