Roman Catholicism and Christian Unity

Christ the Center — Fri, 02 Oct 2026 05:00:00 +0000

Mark Gilbert joins Camden Bucey to examine what Protestants and Roman Catholics mean when they speak of Christian unity. Drawing on Gilbert’s conversion from Roman Catholicism and his work equipping churches to speak with Catholics about Jesus, they contrast a unity grounded in the Spirit’s work through the Word with Rome’s institutional claim to mediate grace and gather humanity into one visible communion.

The conversation turns to Vatican II and Karl Rahner’s doctrine of the “anonymous Christian.” Camden and Mark consider Rahner’s optimistic anthropology, his account of God’s self-communication, and the influence of this framework on Roman Catholic inclusivism. They conclude with a pastoral call to understand Roman Catholicism on its own terms, speak with clarity and charity, and offer the assurance found only in the finished work of Christ.

Mark Gilbert serves in Anglican churches in Sydney. He is a Fellow of the Reformanda Initiative and of the Rome Scholars and Leaders Network (RSLN). His books with Matthias Media include The God Who Saves, The Road Once Travelled, and Stepping Out in Faith. He also hosts Certainty4Eternity.

Resources

Chapters

00:00 Introduction
03:48 Mark Gilbert’s journey from Roman Catholicism
10:50 The Rome Scholars and Leaders Network
15:04 Catholic inclusivity after Vatican II
20:36 Institutional and spiritual views of unity
26:43 The church as a continuing incarnation
28:58 Vatican II and Karl Rahner
35:36 Van Til, Rahner, and the image of God
45:18 The “anonymous Christian”
47:30 Roman Catholicism in a pluralistic world
52:06 Inclusivity, gender, and doctrinal development
58:19 Rahner, Ratzinger, and competing Catholic trajectories
61:28 The Roman Catholic Church as a “sacrament of unity”
65:33 Unity in truth and evangelizing Roman Catholics
70:14 Resources for churches and small groups
72:59 Conclusion

Participants: Camden Bucey, Mark Gilbert

The Nicene Creed and the Nature of Christian Unity

Christ the Center — Fri, 20 Jun 2025 05:00:00 +0000

Leonardo De Chirico and Mark Gilbert join the program to discuss the enduring significance of the Nicene Creed as it marks its 1700th anniversary. Drawing from their recent edited volume, The Nicene Creed: The Nature of Christian Unity and the Meaning of Gospel Words (Matthias Media), the guests explore how shared creedal language can mask deep theological differences, particularly between evangelical and Roman Catholic traditions.

Leonardo De Chirico is a pastor of a Reformed evangelical church in Rome, a scholar of Roman Catholic theology, and a leader in the Reformanda Initiative, which seeks to equip evangelical engagement with Roman Catholicism. Mark Gilbert serves as a chaplain in Sydney, Australia, and leads the ministry Certainty for Eternity, which focuses on evangelism among those from Roman Catholic backgrounds. Both men bring rich theological and pastoral insight to bear on the question of unity in Christ.

The conversation traces the origins of the creed, its Trinitarian framework, and the implications of confessing shared historical truths while diverging in doctrinal substance—especially concerning Christology, the church, and salvation. Leonardo and Mark also share personal insights from their ministries engaging Roman Catholics, underscoring the need for unity rooted in biblical truth rather than institutional alignment or superficial consensus.

This episode invites thoughtful reflection on what true Christian unity looks like in light of Scripture, and how the creeds function as faithful, yet insufficient, summaries apart from a Reformed understanding of the gospel.

Watch on YouTube

Chapters

01:11 Introduction
04:03 Background to the Book
11:27 Can We Have Meaningful Unity with Roman Catholics?
17:31 Unity in Truth
25:32 The Trinitarian Theology of the Creed
29:31 The Christology of the Creed
38:16 The Scope and Usefulness of the Nicene Creed
44:31 The Work of Christ
51:50 Pursuing Christian Unity
57:55 Conclusion

Participants: Camden Bucey, Leonardo De Chirico, Mark Gilbert