Dr. John Jefferson Davis

Chair of the Division of Christian Thought,
Professor of Systematic Theology and Christian Ethics

“What is the role of theology in the life of the church?” Some busy pastors in American churches today might be tempted to answer, “Honestly, not much. I haven’t thought much about ‘theology’ since I left seminary. I’m too busy preparing sermons, attending committee meetings and dealing with conflicts and problems in my church to give much attention to theology.”

However, I would like to suggest that for even such busy pastors, a more accurate image of the role of theology in the life of the parish would not be that of a neglected textbook on the pastor’s shelf, but rather that of a back bone in a healthy body. The backbones in our bodies, like the foundations and electrical and plumbing systems in our homes, are usually taken for granted–until something goes wrong. Like a healthy backbone in a healthy human body, sound biblical theology can provide support, shape and stability to the Body of Christ.

In the early church, the development of Christian theology was shaped by four important functions it served in the life of the church: the catechetical, the apologetical, the polemical and the homiletical. All four of these functions of theology in the early church are still vital for the ministry of the church today. In its catechetical function, theological instruction prepared converts for church membership and participation in the Eucharist, instructing them in basic Christian doctrine. This process of catechesis is often referred to as “discipleship” or “discipling” today. Converts were instructed in the “rule of faith,” a summary of Christian doctrine that formed the basis of the later Nicene and Apostles’ Creeds. Such early summaries of Christian belief are found in the New Testament itself, e.g., Paul’s summary of the kerygma in I Cor. 15:3-5: “For what I received I passed on to you as of first importance: that Christ died for our sins according to the Scriptures, that he was buried, that he was raised on the third day according to the Scriptures, and that he appeared to Peter, and then to the Twelve…”

Augustine’s Enchiridion, or On Faith, Hope, and Love (c.421), was prepared as such a catechetical manual, following the outline of the Apostles’ Creed, the Lord’s Prayer and the two “Great Commandments.” In the preface to his 1560 French edition of the Institutes, John Calvin stated that it was his intention to provide a summary of Christian doctrine that would help Christians in their reading of the Old and New Testaments. Today, new converts and new church members still need to be catechized and instructed in the fundamentals of the faith. Books like John Stott’s Basic Christianity or R.C. Sproul’s Essential Truths of the Christian Faith can assist the pastor in this historic task.

The apologetic task of theology in the early church was to defend and explain the faith to outsiders (cf. I Pet. 3:15, “Be prepared to give an answer to everyone who asks you to give the reason for the hope that is in you”). Early Christian apologists such as Aristides, Diognetus and Tertullian responded to misunderstandings and accusations from the pagans, and Justin Martyr responded to criticisms from the Jews of his day. Thomas Aquinas in his Summa contra Gentiles defended the Christian faith in the face of Muslim criticisms. In today’s religious climate of religious pluralism and the “new atheism,” the need for informed Christian apologetics remains as relevant as ever. Several generations of Christians have been helped by classics such as C.S. Lewis’ Mere Christianity and Miracles. Tim Keller’s The Reason for God provides cogent responses to many of the criticisms of the faith in our own day. In its polemical function, Christian theologians defended and expounded the biblical faith against heretical threats from within the church. Irenaeus, bishop of Lyons, in his massive Against Heresies (c. 185), defended the biblical faith against the threat of Gnosticism, which denied the goodness of the physical creation and placed the biblical story into an alien context of Gnostic cosmological speculation.

In the face of the Arian threat, Athanasius vigorously and tenaciously defended the full deity of Christ, and together with the Cappadocian fathers of the 4th century, laid the basic foundations of Christology and Trinitarian theology that have guided the church ever since. In the modern period, orthodox theologians have labored to preserve the historic Christian faith from the attacks of Enlightenment biblical criticism, deistic denials of miracles and Unitarian denials of the Trinity, original sin and substitutionary atonement.

More recently, revisionist readings of biblical sexual ethics, Dan Brown’s Da Vinci Code, feminist criticisms of the “patriarchal” language of the Trinity and “Open Theism” have questioned or rejected historic orthodox belief. The Pauline admonitions to “watch your life and doctrine closely” (I Tim. 4:16), and for believers not to be “blown about by every wind of teaching” (Eph. 4:14) but to grow mature in the faith, are just as relevant as ever. The fourth function of theology in the life of the early church was the homiletical one: assisting preachers and teachers in the exposition and teaching of Scripture (cf. I Tim. 4:13: “Until I come, devote yourself to the public reading of Scripture, to preaching and teaching”). The church leader is to “hold firmly to the trustworthy message as it has been taught, so that he can encourage others by sound doctrine and refute those who oppose it” (Tit. 1:9).

Knowledge of sound doctrine aids in preaching and teaching not only by the avoidance of heresy, but also by enabling the preacher to place the particular text in the larger context of redemptive history: creation, fall, redemption and new creation. This was precisely what the Gnostics in the early church failed to do, wrenching the biblical texts out of their biblical contexts and placing them in the context of an alien system of thought. Heterodox religious movements today such as the Jehovah’s Witnesses or Mormons can distort the biblical teachings in the same way. Sound teachers in the early church such as Irenaeus, and effective preachers today such as John Stott, John Piper, John MacArthur, Haddon Robinson, Timothy Keller, Gordon Hugenberger, Mark Dever and others have robust theologies that enable them to place the biblical text in its wider redemptive-historical context, and so preserve the distinctive Christian identity of the message.

In addition to these historically recognized functions of theology in the life of the church, a sound biblical theology can provide vitality, vision
and standards for assessment in the local congregation. Church history shows that a robust biblical theology can contribute to church growth and vitality. The opposite is also the case. Churches and denominations that tolerate doctrinal erosion tend to have tepid worship and declining memberships. During the decades between 1965 and 1999, for example, the PC(USA), the United Church of Christ, the Episcopal Church and the United Methodist Church lost, respectively, 40 percent, 29 percent, 26 percent and 24 percent of their total memberships. Growing churches were generally those committed to an orthodox and biblical theology.

As the leader of the flock, the pastor is responsible for casting a vision for the church. The biblical metanarrative of creation, fall, redemption and new creation provides the theological framework and context for such a vision. Salvation itself is not only forgiveness of sins and hope of heaven in the future, but also an experience beginning now of entering into the life of the Triune God. Because of Jesus’ incarnation, death, resurrection, ascension to the right hand of the Father and sending of the Holy Spirit, we—as adopted sons and daughters in Christ—can begin to experience the love of Jesus’ Father for his beloved Son, in the communion of the Holy Spirit, looking forward to its culmination and never-ending deepening in the presence of God in a gloriously beautiful New Creation (Rev. 21, 22). Such a theological vision can energize and unify a congregation, just as John F. Kennedy’s famous vision casting of May 1961,to a joint session of Congress—“A man on the moon by the end of this decade”— energized NASA and the nation for the Apollo space mission.

Finally, sound theology provides a standard for congregational assessment, a basis for asking and answering the question, “How are we doing as a church?” For example, the biblical doctrine of the church, that specifies worship, discipleship and mission as the three God-ordained purposes of the church, then provides the basis for asking questions such as “How well are we worshipping God?”“ Are we as a people growing deeper and more mature in our relationships with Christ and one another?” “How effective are we in reaching out to others—in service and proclamation?” “Are we growing as a church that is ‘deep, thick and different’—deep in our worship and knowledge of the Triune God, ‘thickly’ committed in love and service to one another and distinctive from the secular culture in our beliefs, lifestyle, values and hopes?” Are we growing both in our obedience to the ‘Great Commandments,’ and in our fulfillment of the Great Commission?”

And so it is that theology now, as in the New Testament and subsequent centuries of church history, can play a vital role in the life of a healthy church. As pastors, teachers and lay leaders, may we continue to “teach and admonish with all wisdom, so as to present everyone mature in Christ” (Col. 1:28), and so be able to say with the Apostle Paul at the end of our ministries, “I have fought the good fight, I have finished the race, I have kept the faith” (II Tim. 4:8), in the expectation of that crown of righteousness to be awarded by the Lord to his beloved church.

John Jefferson Davis, Ph.D. a member of the faculty at Gordon-Conwell since 1975, is professor of Systematic Theology and Christian Ethics, and serves as Chair of the Division of Christian Thought. His most recent book is “Worship and the Reality of God: An evangelical Theology of Real Presence (IVP Academic, 2010).