Advent, Eschatology, and the Unity of the Church

I’m posting to hopefulimagination from Regent’s Park College of Oxford University, where I’m serving as a member of the Baptist delegation to the international ecumenical dialogue between the Baptist World Alliance and the (Roman Catholic) Pontifical Council for Promoting Christian Unity. It’s fitting that we’re having these conversations during the deeply eschatological season of Advent, for the Christian eschatological vision is the only thing that can make sense of the otherwise hopeless task of seeking after the visible unity of the church in the midst of its divisions.

The basic premise of New Testament eschatology is this: the reign of God that has come near in Christ is already a present reality, but it is not yet fully realized. That’s the biblical framework for the quest for the unity Christ prayed for his church in John 17. Christians already possess unity in that they belong to the one body of Christ and are indwelt by one Spirit. But as the current divisions of the church attest, this unity is not yet fully realized, for its fullness is not visible. If unity, however, is conceived primarily as a spiritual reality, we may see little reason to devote our energies to the earnest contestation of church-dividing issues of faith and order that must precede visible unity. After all, this unity in Christ and in the Sprit is already a present reality quite apart from any visible manifestations of this unity.

Likewise if visible unity is only fully realized in the age to come, then some may decide there's little or no reason to seek it in the present age. Many Protestants have insisted that the four “marks of the church” in the Nicene Creed, including the oneness of the church, are eschatological marks of the church. That’s true enough. One legacy of this insistence, though, is an aversion to efforts to realize these marks, especially the mark of visible oneness, in the present. But even if the oneness, holiness, catholicity, and apostolicity of the church will fully be realized only eschatologically, that does not mean that the church shouldn’t seek to attain to those marks here and now.

The inadequacy of both of these patterns of relating eschatology to the ecumenical task is apparent in light of an analogous relation of eschatology to the saints’ quest for holiness of life. Even now in this earthly life, the saints already are just that—“holy ones” (Eph. 1:1) who are “seated with him in the heavenly places in Christ Jesus” (Eph. 2:6 NRSV). But in this earthly life the saints are not yet fully holy in person or practice. The completion of sanctification awaits the “eternal weight of glory beyond all measure” (2 Cor. 4:17).

Just as the present positional holiness of the saints in Christ does not warrant a refusal of the sanctifying work of the Spirit in the present, and just as the deferral of the glorification of the saints until the resurrection should not de-motivate the present pursuit of the sanctification that will be completed in the eschaton, so it is with the already / not-yet nature of Christian unity. Because we’ve already been entrusted with the lasting reality of oneness in Christ and in the Spirit, we must seek to make this oneness visible to the world in advance of the age to come. And because visible unity is a vision of the last things disclosed by Jesus himself, we can be confident that when we take action to seek the visible unity of the church, we’re joining God in what God intends to do in and through the church in the culmination of God’s goals for all things.

May it be so. How long, O Lord, until it is? Come, Lord Jesus, come.

Steven R. Harmon teaches Christian Theology at the Gardner-Webb University School of Divinity in Boiling Springs, North Carolina, and is the author of Ecumenism Means You, Too: Ordinary Christians and the Quest for Christian Unity (Cascade Books, 2010). This blog post is adapted from a chapter he contributed to A Century of Prayer for Christian Unity, ed. Catherine E. Clifford (Eerdmans, 2009).