This volume consists entirely of materials posted on my website / blog: "Biblical Evidence for Catholicism": written between 1997 and 2011: several in direct response to Protestant queries or challenges. I've revised them in order to clarify the thoughts and to "tighten" up the arguments. My goal is to defend and clarify what Catholics believe with regard to ecclesiology, or the doctrine of the Church (including the papacy), why we do, and to demonstrate that Catholic beliefs are in harmony with Holy Scripture and the doctrines held by the early Church. Protestants deny the infallibility of the Church, and hold that Scripture alone is the only final, infallible authority (denying that characteristic to the Church and apostolic tradition and the papacy). Therefore, if Catholics can show that an infallible Church and papacy are squarely based on Scripture, Protestants would be bound to those beliefs, by their own rule of faith (sola Scriptura). My aim is to demonstrate exactly that.