This book investigates the validity of the 'urban thesis,' which posits that early Christianity expanded primarily through urban centers, by testing its demographic and historical feasibility. Thomas A. Robinson, a scholar of early Christian history, utilizes demographic modeling and historical analysis to challenge the prevailing academic consensus. He argues that if the urban thesis were accurate, the resulting population density of Christians would have rendered the existence of other religious groups in Roman cities statistically impossible. The author proposes that the rural landscape, rather than the city, served as a more significant, yet overlooked, catalyst for the growth of the early church.

Scholars and historians frequently cite this work as a necessary corrective to urban-centric models of early church growth. Readers often note the academic rigor and the logical clarity with which Robinson dismantles established historical assumptions.