In this book, Karly Poyner-Smith approaches the ExVangelical movement from the perspective of a purity discourse scholar to examine purity as a discourse in religious and non-religious spaces of contemporary culture.

American evangelicalism and its sub movements remain a considerably large component of Western culture and politicism. ExVangelicals openly ask questions of American evangelicalism's relationship to race, gender, sexuality, disability, and nationalism, which are all locatable in the religious doctrine's usage of purity. Therefore, to extract oneself from the discourse of purity one grew up learning and subscribing to during the purity culture movement, one must endeavor to question and reformulate layers of previous doctrinal beliefs. This is imaginatively messy, involved, and laborious, and from a rhetorical perspective, this act is performed when ExVangelicals use their identity to excavate and encounter concepts of purity, thus creating a rhetoric of impurities.

Poyner-Smith's rhetorical analysis of this movement allows readers to further understand purity's influence in everyday rhetoric beyond the religious and historical field. Additionally, the author provides examples of how readers can take the ExVangelical example of a rhetoric of impurities and apply it to non-religious spaces that the target audience most likely interacts within daily. These include topics of healthism, feminism, the college classroom, and heteronormativity. While she examines ExVangelical narratives (such as interviews with ExVangelicals, dairies, and published memoirs) as rhetorical text, her emphasis is on what a larger audience can take away and apply in effort to engage with liberatory rhetorics no matter their proxemics to evangelicalism.