We're not going to stop any presses by declaring that Christianity has suffered serious decline in Europe—the place where apostles preached, and where Aquinas, Calvin, Luther, Barth, and countless other spiritual luminaries called home. Witness, to take just one example, the current sad turmoil in the Anglican Communion between the theological liberals of the statistically stagnant British mother church and their conservative brethren in rapidly growing, vibrant African and Asian dioceses.

Until recently, many Western academics accepted the sociologists' "secularization thesis," which asserts that intellectual advance and economic modernization lead people and nations past a need for faith, to a more enlightened and more secular mode of life. Europe's ongoing and increasing contempt for organized religion has been their prime example, while the growth of Christianity in countries such as Nigeria and China have been dismissed as a primitive stop on the road toward a godless society.

Perhaps no nation more proudly flaunts its secularism than France. The land that launched the millennium of Christendom by crowning Charlemagne Holy Roman Emperor in 800 has morphed into a staunchly secularist state, opposed to even the most cursory mention of Christianity's historic influence in the European Union's recently drafted constitution. Over the years France has exemplified the convergence of academic skepticism and popular unrest that has produced empty church pews across the continent.

But events have thrown the secularization thesis into disrepute—to the point where few now defend it in its original form. At the crux of this intellectual shift is one piece of glaring counter-evidence: the United States of America. American Christianity has survived and thrived despite suffering many of the same factors that have proved so troubling to Europe. Americans have been dragged into modernity by scientific advance, brutalized by modern mechanized warfare, battered by urban squalor, seduced by consumerist materialism, and bombarded by anti-Christian critiques from a secularist media and academic establishment. But through it all, they have clung to faith and resisted the destructive ideologies that so deeply scarred twentieth-century Europe.

Alexis de Tocqueville, one of the most famous links between France and the United States, illuminated American Christianity's cultural resilience. During his trip to the United States in 1831, he found a vibrant, flourishing crop of denominations and churches. These, he insisted, "all agreed with each other except about details." All agreed, too, that "the main reason for the quiet sway of religion over their country was the complete separation of church and state." Tocqueville claimed that throughout his stay in America, he met "nobody, lay or cleric, who did not agree about that."

While no single factor can exhaustively explain the stark differences between these Western strongholds, the contrast between Europe's long legacy of government-sponsored religion and America's historically recent and unique separation of church and state provides one wide window on European Christianity's decline.

Constantine Launches the Long Era of Church-State Unity

Constantine's conversion in 312 looms large for the study of church-state relations. During the early church era Tertullian famously said, "The blood of martyrs is the seed of the church," but after Constantine saw his vision at Milvian Bridge the empire that formerly shed Christian blood began conquering behind the cross. Suddenly, Christian faith became a stepping-stone to secular success, and those who yearned to become truedisciples began to feel they could only do so if they first escaped the compromised "Christian" cities into desert caves and monasteries.

Scholars have frequently debated the motivations behind Constantine's bold actions, including his decision to call the landmark Council of Nicea in 325. Yet whether his motivations were political or spiritual, Constantine set a precedent of political influence over church issues that has been abused by numerous European leaders over the centuries. His successor, Constantius, understood the political expediency of religious power when he petitioned church officials to equate his decisions with God's commands.

Of course, we would be foolish not to acknowledge how God utilized the Roman Empire's remarkable territorial reach—and thus the spread of its sponsor faith. Establishment proved fruitful for the church's evangelistic efforts as the Romans carried Christianity's banner to the farthest and most barbaric reaches of their vast empire, establishing the foundations of what would later develop into Christendom.

Yet from its inception, Christendom suffered the ill effects of the church's intimate relationship with the state. While in an environment of open religious competition American Protestant denominations have thrived both in numbers and—often—in spiritual health, European Christianity's disputes have historically proven bloody and spiritually costly.

Take for example the Great Schism of 1054, when Eastern and Western Christianity became formally divided. The estrangement between the two had been deepening for centuries—and it was as cultural and political in nature as it was theological. Then, to add military insult to ecclesiastical insult, an army of Western Christian Crusaders led by money-hungry Venetian merchants pillaged Constantinople during the Fourth Crusade in 1254, critically weakening that city's defenses. In the end, the division from the West so weakened the East that they were unable to resist the Muslim invaders who captured Constantinople in 1453. Soon, having breached Christendom's eastern flank, Muslim armies threatened Christian Europe itself, even to the gates of Vienna.

Rome's fall, Constantinople's forsaking, and Christendom's eventual collapse during the Reformation era's wars of religion reveal the perils of uniting the church so closely with temporal earthly regimes. Bluntly put, the church that lives by state power, dies by state power—its fortunes are too closely tied to political vicissitudes.

Roots of Europe's Twentieth-Century Religious Discontent

The French Revolution exemplifies the dangers faced by a church tied to an unpopular government, but France also birthed the Enlightenment criticism that eroded church support from Europe's educated elites. When Frenchmen renamed the Cathedral of Notre Dame the Temple of Reason in 1793, they expressed distaste for their nation's Catholic heritage and unswerving faith in the supremacy of human thought. Though Catholicism in France did not die with the Revolution, and the cathedral's name was later restored, French academics like Voltaire and Rousseau drew upon the scientific discoveries of Isaac Newton and others to build a rationalistic worldview, elaborated by later scientists such as Charles Darwin.

As the attack on faith by the intellectual elite continued, Christianity began losing Europe's working classes en masseduring a series of secular crises, beginning with the urban squalor created by the rapid industrialization of the nineteenth and early twentieth centuries. Shocked by the tremendous human toll of World War I, Europe's masses began turning toward other ideologies, especially socialism, which they perceived could speak more directly to their everyday circumstances than a seemingly irrelevant state-church.

The most dramatic example of this shift is Russia's communism; others include Nazism in Germany and fascism in Italy and Spain. With the world so quickly changing around them, Europeans revolted against static institutions they accused of either causing or failing to minister to their sufferings. In most cases they directed venom toward secular governments, many of which still ruled co-dependently with the established church.

While so many of the European church's challengers over the years, from rationalism to socialism to New Age religions, have died or lost steam, Europeans have shown little interest in returning to the church. Meanwhile, Americans look across the ocean and wonder what they should learn from Europe's example. For starters, they can thank God that American churches remain independent of secular authorities.

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