This exploratory paper seeks to develop a methodology for theological engagement with popular music in the public sphere. What is the significance of popular music for theology? What contribution to our understanding of popular music can theology make? What is the significance of a theological engagement with popular music in the context of a post-secular public sphere? These are some of the key questions that lie behind the discussion in this paper, which takes the music of Lady Gaga as a worked example on account of its rich religious symbolism, multiple references to Christianity and huge popularity.