The Classical and Reformed Marks of the Church: A Theological Exploration

J. Neil Daniels 

Introduction

The nature of the true Church has been a defining question in Christian theology, shaping ecclesiological debates across centuries. The Niceno-Constantinopolitan Creed (381 A.D.) confesses the Church as “one, holy, catholic, and apostolic,” establishing these as the four classical notae ecclesiae (marks of the Church). During the Protestant Reformation, Reformed theologians supplemented these with additional criteria to identify the visible Church amid perceived institutional corruption. This essay explores the theological foundations, historical development, and enduring significance of both the classical and Reformed marks, offering a framework for discerning the Church’s identity in both its spiritual essence and visible expression.

The Four Classical Marks of the Church  

The Nicene Creed’s four marks—oneness, holiness, catholicity, and apostolicity—articulate the Church’s essential nature as a divine institution rooted in Christ’s redemptive work. These marks are not mere organizational traits but theological realities that reflect the Church’s identity as the body of Christ, animated by the Holy Spirit.

Oneness

The Church’s unity flows from its union with the triune God, as Christ prayed that believers “may be one” as He and the Father are one (John 17:21). This unity is spiritual, grounded in a shared faith and participation in Christ, yet it seeks visible expression through common confession and sacramental fellowship (Eph 4:4–6). Despite historical schisms, the Church remains mystically one, transcending denominational divides through its gospel fidelity and eschatological hope of perfect unity in Christ.

Holiness

The Church is holy because it is consecrated by God, set apart for His purposes through the indwelling of the Holy Spirit (1 Cor 1:2). This holiness is not rooted in the moral perfection of its members but in Christ’s righteousness, imputed to believers and progressively realized through sanctification (Eph 5:26–27). The Church’s holiness thus reflects both its divine calling and its ongoing transformation.

Catholicity

Catholicity, derived from the Greek katholikos (“universal”), signifies the Church’s transcendence of cultural, geographic, and temporal boundaries. It embraces all peoples and epochs, fulfilling Christ’s commission to make disciples of all nations (Matt 28:19; Rev 7:9). Catholicity also implies doctrinal wholeness, as the Church preserves the fullness of truth revealed in Christ, guarding against partial or sectarian expressions of faith.

Apostolicity

The Church is apostolic because it is built on the foundation of the apostles’ teaching, infallibly preserved in the God-breathed Scriptures (Eph 2:20; 2 Tim 3:16–17). Apostolicity does not require an unbroken chain of episcopal succession but demands fidelity to the gospel as proclaimed by the apostles. This mark ensures the Church’s continuity with its founding revelation, anchoring its mission in the authority of Christ’s commissioned witnesses.

These classical marks, affirmed across Christian traditions, provide a theological lens for evaluating the Church’s identity and mission, uniting diverse communions in a shared confession of its divine origin.

The Reformed Marks of the True Church  

The Protestant Reformation, responding to the clear deviations in the medieval Church, prompted Reformed theologians to articulate three additional marks to identify the visible Church where it authentically exists. Drawn from Scripture and patristic tradition, these marks emphasize the Church’s fidelity to its divine calling in practice.

Pure Preaching of the Word

The foremost mark is the faithful proclamation of God’s Word, through which the Holy Spirit gathers and sustains the Church (Rom 10:17; 1 Pet 1:23). For John Calvin, the pure preaching of Scripture is the heartbeat of the Church, distinguishing it from institutions that obscure divine revelation with human traditions (Institutes, 4.1.9). This mark ensures that the Church remains anchored in the gospel, fostering faith and guarding against doctrinal error.

Right Administration of the Sacraments 

The two sacraments (better, ordinances)—Baptism and the Lord’s Supper—are visible signs of God’s grace, instituted by Christ to confirm the promises of the gospel (Matt 28:19; 1 Cor 11:23–26). The Reformers insisted on their administration in accordance with Scripture, rejecting both the Roman Catholic multiplication of sacraments and radical Protestant tendencies to diminish their significance. Properly administered, the sacraments strengthen the Church’s identity as a covenant community.

Exercise of Church Discipline

Church discipline, though often overlooked, is essential for maintaining the Church’s holiness and integrity (Matt 18:15–20; 1 Cor 5:1–13). Calvin described it as the “sinew” of the Church, binding its members to doctrinal and moral accountability. Discipline distinguishes the Church from secular organizations, preserving its witness by addressing sin and fostering repentance within the community.

These marks, enshrined in confessional standards like the Belgic Confession (Article 29) and the Second Helvetic Confession (ch. 17), complement the classical marks by providing practical criteria for recognizing the Church’s visible presence in a fallen world.

Theological Interconnection of Classical and Reformed Marks

The Reformed marks are not a rejection of the Nicene marks but their practical expression in the Church’s visible life. The pure preaching of the Word fosters the Church’s oneness by uniting believers around a shared confession. Discipline upholds holiness by calling the community to live in accordance with its divine calling. The sacraments advance catholicity by incorporating diverse peoples into the universal body of Christ. Apostolicity is preserved through fidelity to the apostolic gospel, proclaimed and enacted in Word and sacrament. Together, these marks bridge the invisible essence of the Church with its tangible embodiment, offering a robust framework for ecclesial discernment in contested times.

Contemporary Relevance of the Marks 

In an era of theological pluralism, ecclesiastical fragmentation, and cultural pressures, the classical and Reformed marks remain vital for discerning the true Church. Churches should not be judged by numerical success, cultural relevance, or institutional power but by their adherence to these scriptural and theological standards. The emphasis on the Word counters relativism, grounding the Church in divine truth. The sacraments anchor worship in Christ’s redemptive work, resisting trends toward entertainment-driven gatherings. Discipline, though countercultural, preserves the Church’s distinctiveness, ensuring its witness shines in a world prone to moral ambiguity.

The marks also challenge contemporary divisions, calling churches to pursue visible unity through shared fidelity to the gospel rather than institutional consolidation. They invite reflection on how the Church can embody its catholicity in a globalized world, engaging diverse cultures while remaining rooted in apostolic truth.

Conclusion

The classical marks of the Church—one, holy, catholic, and apostolic—provide a timeless confession of its divine identity, while the Reformed marks—pure preaching, right administration of the sacraments, and church discipline—offer practical criteria for its visible expression. Together, they form a comprehensive ecclesiological framework that guides believers in recognizing and participating in the Church that Christ founded (Matt 16:18). In a world marked by confusion and division, these marks remain a beacon, calling the Church to embody its calling with clarity, fidelity, and hope.

For Further Study 

Patristic Sources

Cyprian of Carthage. On the Unity of the Church. Translated in The Fathers of the Church series, Vol. 36. Washington, D.C.: Catholic University of America, 1958.

~ A key early work addressing unity and catholicity.

Augustine. On True Religion and The City of God.

~ Foundational reflections on the Church’s holiness, unity, and relation to the broader culture.

Primary Sources and Historic Confessions

Calvin, John. Institutes of the Christian Religion. Translated by Henry Beveridge. Peabody: Hendrickson, 2008.

~ Especially Book IV, chapters 1–2 on the nature and marks of the Church.

The Belgic Confession (1561). Article 29: "The Marks of the True Church."

Second Helvetic Confession (1566). Chapter 17: "Of the Catholic and Holy Church of God, and of the One Only Head of the Church."

The Westminster Confession of Faith (1646). Chapters 25–26 on the Church.

Primary Systematic Theologies 

Bavinck, Herman. Reformed Dogmatics: Abridged in One Volume. John Bolt, ed. Grand Rapids, MI: Baker Academic, 2011. 601–05.

Garrett, James Leo, Jr. Systematic Theology: Biblical, Systematic, and Historical, 2 vols. 

1990–95. Reprint. Eugene, OR: Wipf & Stock, 2014. 2:522–24.

Grudem, Wayne. Systematic Theology: An Introduction to Biblical Doctrine. 2nd ed. Grand Rapids, MI: Zondervan, 2020. 1060–62.

Harwood, Adam. Christian Theology: Biblical, Historical, Systematic. Bellingham, WA: 

Lexham Academic, 2022. 648–74.

Letham, Robert. Systematic Theology. Wheaton, IL: Crossway, 2019. 790–91.

Other Works 

Allison, Gregg R. 50 Core Truths of the Christian Faith: A Guide to Understanding and Teaching Theology. Grand Rapids, MI: Baker, 2018. 283–90.

Clowney, Edmund P. The Church. Contours of Christian Theology. Downers Grove, IL: 

IVP, 1995. 99–115. 

Dulles, Avery. “The Church as One, Holy, Catholic, and Apostolic.” Evangelical Review of Theology 23.1 (1999) 14–28.

George, Timothy. “Toward an Evangelical Ecclesiology.” In Catholics and Evangelicals: 

Do They Share a Common Future? Thomas P. Rausch, ed. Downers Grove, IL: IVP, 2000. 122–48.

Hammett, John S. Biblical Foundations for Baptist Churches: A Contemporary Ecclesiology. 2nd ed. Grand Rapids, MI: Kregel Academic, 2019. 57–73. 

Hiscox, Edward Thurston. The New Directory for Baptist Churches. Philadelphia, PA: 

American Baptist Publication Society, 1894. 31–5. 

Roark, Dallas M. The Christian Faith: An Introduction to Christian Thought. Grand Rapids, MI: Baker, 1969. 260–67. 

Zuber, Kevin D. The Essential Scriptures: A Handbook of the Biblical Texts for Key Doctrines. Chicago, IL: Moody, 2021. 292–94. 

Traditional Notae 

Hammett, John S. Biblical Foundations for Baptist Churches: A Contemporary Ecclesiology. 2nd ed. Grand Rapids, MI: Kregel Academic, 2019. 57–69. 

Reformational Notae 

Hammett, John S. Biblical Foundations for Baptist Churches: A Contemporary Ecclesiology. 2nd ed. Grand Rapids, MI: Kregel Academic, 2019. 69–73.