How the Enlightenment Transformed Christian Theology.

Written by Hannah Hammond

The period known as the Enlightenment (roughly 1685–1815) is often characterized in Christian history as the great antagonist of faith—a moment when pure reason challenged and attempted to undermine divine revelation and religious tradition. The medieval synthesis, in which the Truth of Christianity was largely unquestioned within Christendom, fractured under the pressure of new philosophical inquiry.

However, this traditional portrayal—as a simple rebellion against religion—requires significant re-evaluation. While the Enlightenment undeniably challenged religious orthodoxy, it was also profoundly complex. It was a movement a product of religious debate rather than rebellion against it. In fact, it contributed directly to the Evangelical Revival and the emergence of modern evangelicalism, fostering new iterations of faith.

The Enlightenment forced the Western Church to fundamentally transform its worldview from medieval to modern. By examining key areas like authority, tolerance, and biblical interpretation, we can see how this age of reason did not destroy Christianity but instead refined Christian dogma and prompted much-needed pioneering work.

1. The Challenge to Authority: Redefining Orthodoxy

The Enlightenment marked a cultural shift that promoted a distinctive self-awareness in the West, resulting in long-standing tradition and established authority being heavily challenged.

Thinkers like Jean-Jacques Rousseau (1712–78) advanced the radical theory that governmental laws were not appointed by God but were derived from the general will of the people. This secularized premise threatened the church’s dominance by undermining humanity’s dependency on God. The new criteria of orthodoxy became the model of scientific enquiry.

It is important to note that the Enlightenment was not wholly secular. It developed within the confines of religious tradition where secular and religious ideas maintained a constant interplay. Even critics of the church, such as Voltaire (1694–1778), paradoxically believed that belief in God is necessary for the preservation of everyday morals. This demonstrates that religious thought remained deeply embedded socially, historically and culturally, proving that the Church continued to provide the framework for the modern age.

2. The Groundbreaking Shift Toward Tolerance

One of the most defining characteristics of the Enlightenment was the rise of increasing tolerance. Following the devastating religious warfare of the Reformation era, which was formally ended by the Peace of Westphalia (1648), religious differences were no longer viewed as justification for conflict.

Religious enlighteners embraced this shift, rearticulating their faith using contemporary science and philosophy to promote tolerance as an essential part of their belief. This commitment to tolerance led to the Toleration Act (1689), which affirmed the individual’s right to choose their faith. Key theological figures drove this intellectual shift:

• Pierre Bayle (1647–1706) radically advocated for tolerance for all denominations, including Jews, Muslims, and—at the time, controversial—atheists.

• John Locke’s Letter on Toleration (1689) provided an important intellectual foundation of religious belief in modern democracies.

Despite limitations (Locke, for instance, did not tolerate atheists or Catholics), the liberalization of thought within the churches due to their active commitment to advocating tolerance was groundbreaking. Today, religious pluralism is accepted and commonplace in Western society.

3. Evangelicalism: A Modern Movement Shaped by the Age

Perhaps the most surprising influence of the period was on evangelicalism, which was born out of an expression of the Enlightenment and permeated by Enlightenment influence.

Evangelicals shared the Enlightenment’s characteristic optimism regarding the future and demonstrated great confidence in progress through social reform. This spirit manifested in widespread philanthropic activity, including the missionary movement and the anti-slavery campaign, aligning the movement in harmony with the spirit of the age. Furthermore, figures like Jonathan Edwards (1703-1758) derived his confidence of salvation from the mood of the Enlightenment.

However, this alignment came with a theological warning:

The church, by adopting Enlightenment assumptions, has sometimes subdued the gospel message, inclined to adapt to culture rather than offering something distinctly different. This adaptation is most clear in the understanding of truth. Evangelicalism has sometimes erred by equating the biblical concept of truth with the Enlightenment notion of western propositional agreement. The movement is now challenged to rediscover the distinctiveness of the biblical concept of truth. Due to its reliance on an outmoded presentation of truth as purely objective, evangelicalism can appear dogmatic and offensive to postmodern religious pluralism.

In contrast to pure rationalism, figures like Blaise Pascal (1623-62) argued that God is known only through Jesus by faith, and John Wesley (1703-1791) encouraged plain speaking, recalling people to the divine power of faith that could transform lives. This shows that the Enlightenment was arguably conducive to Christian spirituality rather than a hindrance.

4. Apologetics and the Market of Relativism

The Enlightenment, particularly through the work of the British empiricist John Locke (1632-1704), put pressure on Christianity by arguing that it was rational and could be derived from reason itself. This fundamentally altered the church's mission, obligating Christianity to develop sophisticated apologetics that operated within the Enlightenment paradigm of reason.

When scholars began to identify discrepancies, the apologetic response used methods of reason to appeal to proofs of God’s existence, the trustworthiness of Scripture, and the historicity of Jesus’ resurrection.

However, the consequences of this strategic choice were challenging. By incorporating scientific apologetics into theology, the church attempted to defend the reasonableness of Christianity, which often resulted in the domesticating of Christianity from Enlightenment ideals within the prevailing intellectual environment, or ‘reigning plausibility structure’. The danger here is profound: Christianity risked becoming another product on the market of relativism.

5. Biblical Scholarship: From Textbook to Living Story

Under the weight of Enlightenment scrutiny, the reasonableness of Christianity rested heavily on Scripture. Yet, the medieval assumption of synthesizing religious and scientific truths began to fracture. New scientific methods, such as the advancement of geology and biology, challenged the historical veracity of the creation accounts in Genesis.

Critics like Baruch Spinoza (1632-1677) viewed the Bible not merely as divine revelation but as a historical and cultural human product. This forced Scripture to justify itself before the bar of reason.

Fortunately, religious enlighteners provided a crucial defense. They rejected the view of the Bible as a “textbook of science” and defended the authority of biblical revelation by viewing the narrative as a living story rather than as a set of propositions. Scholars such as Richard Simon (1638-1712) and Johann Salomo Semler (1725-91) interpreted Scripture historically, recognizing the “necessity and complexity” of translating an ancient worldview for a modern one. Because of this pioneering work, biblical criticism is now considered essential for understanding the biblical message in the modern light, rather than a threat to revelation.

Conclusion: A Refined Faith for a Modern World

The effect of the Enlightenment on the Western Christian church was absolute and profound, irreversibly transforming the way we view God and ourselves from a medieval framework to a modern concept.

Traditional authority was no longer determinative, but the age of freedom and reason promoted religious pluralism and questioning. Far from having a negative effect that resulted in the elimination of religion, the challenges presented by the Enlightenment refined Christian dogma and cultivated acceptance of religious pluralism. The necessity of competing with other ideologies forced the church into much-needed pioneering work, aligning modern evangelicalism with the progressive spirit of the age.

You can find the books referenced in this article listed in the bibliography below.

Bibliography

Barnett, S. J. The Enlightenment and Religion: The Myths of Modernity. Manchester: Manchester University Press, 2003.
Bebbington, D. W. Evangelicalism in Modern Britain: A History from the 1730s to the 1980s. London: Routledge, 2002.
Byrne, J. M. Religion and the Enlightenment. Louisville: Westminster John Knox Press, 1996.
Drane, J. What is the New Age Still Saying to the Church? London: Marshall Pickering, 1999.
Dreyer, F. ‘Faith and Experience in the thought of John Wesley’, American Historical Review, vol. 88, no. 1, 1983.
Hampson, N. The Enlightenment. London: Penguin Books, 1990.
Eves, A, and C. Gempf. ‘Presenting the Challenge: Christ and Culture’ in London Bible College Authors, Christian Life & Today’s World. Bletchley: Scripture Union, 2002, 13-27.
McGrath, A. E. Evangelicalism and the Future of Christianity. London: Hodder & Stoughton, 1988.
McGrath, A. E. Historical Theology. West Sussex: Wiley-Blackwell, 2013.
McGrath, A. E. A Passion for Truth. Illinois: IVP, 1996.
Newbigin, L. The Gospel in a Pluralist Society. London: SPCK, 2014.
Pascal, B. Pensées and Other Writings. Oxford: Oxford University Press, 2008.
Pocock, J. G .A. Barbarism and Religion: The Enlightenments of Edward Gibbon, 1737- 1764. Cambridge, UK, 1999.
Sire, J. W. Naming the Elephant. Illinois: IVP, 2004.
Sorkin, D. The Religious Enlightenment. New Jersey: Princeton University Press, 2008.

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