What Is Christian Unity?

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, Australia. 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, Stepping Out in Faith, and Talking with Catholics About Jesus. He also hosts Certainty4Eternity.

Conference Address: Camden Bucey

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The covenant of grace has its source in eternity, in the covenant of redemption: the eternal agreement of Father, Son, and Spirit to save a people. In “Before the Foundation of the World: The Covenant of Redemption and the Covenant of Grace,” given at the recent 2026 Reformed Forum Theology Conference, Camden Bucey traces the historical covenant of grace back to that eternal counsel. Following Herman Bavinck, he shows that the covenant revealed in time rests on an unchanging foundation in the counsel of the triune God.

Before creation and before the fall, God purposed one redemption with one Savior at its center, and the unity and certainty of the covenant of grace rest on that purpose. This opening address gathers up the first two conferences in the trilogy and lays the foundation for the addresses that follow.

The rest of the conference addresses will be released soon.