This paper looks at some essential themes in post-apostolic Christianity through the epistolary interventions of Clement of Rome, Ignatius of Antioch, and Polycarp of Smyrna. Each of these writers led churches in one of the three most important regions of the Roman Empire and the emerging geography of early Christianity. Though their letters were occasional and directed at particular contextual situations, they reflected significant responses to challenges threatening the inherited ecclesiastical status quo. In defending the inherited ecclesial tradition, they also clarified and expanded these traditions and set the churches on a trajectory that would culminate in the monepiscopate as it came to be more clearly defined in the age of Hippolytus and Cyprian in the early third century. Concepts like apostolic succession (or imitatio), the church’s relationship to Judaism (and the synagogue), the authority of the scriptures (along with NT texts), the role of the Holy Spirit, the nature of worship, and the structure of the church’s leadership (along with titles and divisions of responsibilities), all emerge in these writings by the three leaders who likely knew (or knew of) each other. How they resolved conflict and division in their churches sheds light on some of their inherited ecclesial traditions and informs their prescriptions for its evolution in the future.