As we have been considering the nature of the church as described in the Apostles’ Creed and affirmed by the Reformers, we have seen that the marks of the church given in the creed have an already and not-yet aspect to them. With respect to the church’s unity, the church is already one but not yet fully united in the faith, since we are growing together toward greater unity (Eph. 4:1–16). Having been set apart from the world, the church is already a holy nation, but we are not yet completely holy because we are growing in our sanctification (1 Peter 1:13–16; 2:9). Even now, the church is universal, being made up of people from around the globe; however, the church is not yet as catholic as it should be because there are still tribes that have not been reached with the gospel (Acts 15:1–21; Rev. 7).
Regarding the final defining element of the church according to the Apostles’ Creed—Apostolicity—the already/not-yet tension also holds true. First, we must consider what it means that the church is Apostolic. It means being in continuity with the faith and practice of the Apostles. The overriding concern of the early church, when the Apostles’ Creed was first written, was to demonstrate its adherence to what the Apostles taught. While at points the fathers may have not followed Apostolic teaching, their desire to be Apostolic is instructive. Our goal as the church is not to be innovative; it is to hold fast to the faith once delivered to the saints by the Apostles, who were appointed by Christ to be His agents of revelation (Jude 3).
We find the biblical foundation for this understanding of the church’s Apostolicity in texts such as Ephesians 2:19–22. Paul explains that the “household of God”—the church—is “built on the foundation of the apostles and prophets” (v. 20). The foundation of a building provides the stability for the structure; without a secure foundation, a building will crumble. So it is with the church. A church that is not built on the foundation of the teaching of the Apostles and prophets—the divine revelation of the Scriptures—will not endure in faithfulness to Christ.
Because of sin and our ever-growing understanding of God’s Word, the church can always be more Apostolic. So, the second way the church manifests its Apostolicity is in its desire to hew ever closer to the Apostolic teachings given in Scripture. As we stand on the Scriptures, we are an Apostolic communion, and as we seek to reform our faith and practice according to the Word of God, the church better reflects the Apostolicity we profess.
All of God’s people have a responsibility to ensure the Apostolicity of the church. Pastors, elders, and teachers must faithfully exposit the Word of God to their congregations. Laypeople must not tolerate the teaching of heresy in their midst. Yet, to ensure that the church remains Apostolic, we must know Apostolic teaching ourselves. That can be accomplished only through the regular study of the Scriptures.