Why do Catholics look to the Pope and the Magisterium for ultimate authority, while Protestants look to Scripture alone—and what does that mean for everyday faith? 

Mark continues the “Why Protestantism?” series by examining the heart of the authority debate. He explains how Roman Catholicism understands the Pope, apostolic succession, sacred tradition, and the Magisterium, and why Catholics believe these provide an infallible guide for the Church. Mark then contrasts this with the Protestant conviction that the Bible alone is the final and sufficient authority for faith and life.

Mark explores where these two systems diverge, why the Reformers rejected papal infallibility, and how the question of authority shapes everything—from doctrine, to worship, to the clarity of the gospel itself. This episode sets the stage for next week’s focus on gospel clarity and why authority matters for every Christian.

Episode Highlights

00:00 — Framing today’s question: who speaks with final authority in the Church?
02:14 — How Catholicism understands authority: Scripture, tradition, and the Magisterium
04:41 — Apostolic succession and why Catholics believe the Pope is Peter’s successor
06:58 — What papal infallibility actually means (and what it doesn’t)
10:08 — Ex cathedra teaching: when the Pope speaks infallibly
12:15 — Protestant concerns: where is the biblical basis for an infallible papacy?
14:02 — Why the Reformers insisted on sola Scriptura (Scripture alone)
16:40 — The practical implications: how these differences shape the Christian life

Resources:

• Cornerstone Church Sermons: Listen online
• Gavin Ortlund, What It Means to Be Protestant (Truth Unites)
• Matthew Barrett, The Reformation as Renewal
• Michael Svigel, RetroChristianity: Reclaiming the Forgotten Faith
• Chad Van Dixhoorn (ed.), Creeds, Confessions, and Catechisms: A Reader’s Edition
• Catechism of the Catholic Church (Vatican)