The Enlightenment was a seventeenth- and eighteenth-century international movement in ideas and sensibilities, emphasizing the exercise of critical reason as opposed to religious dogmatism or unthinking faith. It developed along with the rise of scientific thinking independent of religious thought and stressed the importance of nature and the natural order as a source of knowledge. In reaction to the religious wars of Europe, Enlightenment thinkers defended religious tolerance and religious freedom. Their emphasis on intellectual freedom and human rights led to a conflict between the advocates of these new ideas and the political and religious establishments in Europe, most dramatically in France.
The Enlightenment in America, more moderate than in Europe, influenced both religious and political thought throughout the colonies. Many would argue that its approach to religious tolerance rose to prominence in America in large part because no single religious group could garner the necessary votes to impose themselves upon the fledgling republic. Leaders such as Thomas Jefferson and Benjamin Franklin were considered paragons of Enlightenment thought, and the freedom-loving religious rationalism of their ideas helped to lay the foundations of the Declaration of Independence and the Constitution of the United States.
The Enlightenment also bred religious controversy. Many of its advocates, many of whom were themselves Christian, often dismissed the new revivalist religion of the Great Awakening as emotionally excessive. Evangelical Protestants, on the other hand, often viewed rationalism, religious tolerance, and other enlightenment ideals as dangerous to piety and national solidarity in the budding republic. Historians have usually cast this controversy in terms of a conflict between those who favored rational religion and those who opposed them by defending an emotional religion of the heart. But the Enlightenment was so pervasive in the colonies that few Americans remained wholly untouched by its spirit.
Both the emotionalism of revivalist religion and the reasoned ideals associated with the Enlightenment played important roles in the American Revolution. Revolutionaries were drawn from all religious camps and most of them shared a common commitment to freedom of religion. Most—though certainly not all—revolutionaries, however, fought not for religious freedom for all, but rather for their particular sects or denominations. Nonetheless, the impact of the Revolution and the subsequent adoption of the Constitution on American Christianity cannot be overstated. This period laid the foundation for a bold experiment in religious freedom unlike any understandings of state-religion relations at the time.
The Constitution banned the “establishment” of religion by the state, thus forcing both Anglicans and Congregationalists to abandon their traditional prerogatives of state support, a bold departure from tradition. All churches and other religious organizations that had arisen during the colonial period necessarily reconstituted themselves under the new constitutional guidelines. This, however, until as late as the 1830s, was understood to apply to the federal government alone; states were allowed to decide for themselves whether or not to have state-supported churches. In any case, this outlook, which considered all churches equal before federal law, more or less asserted that churches are voluntary organizations with no formal coercive authority over those who did not wish to belong to them.
The Revolution and the Constitution became part of the “myth” of America, the powerful foundational story told about America’s origins. This story begins with the vision of creating a new Christian society on American soil and moves to the idea of a society based on commitment to religious freedom. Still, the transcendent and purposeful vision of America’s destiny remained. This vision fostered the development of what has come to be called America’s “civil religion”: a belief in America’s special mission as a society based on equality before the law, freedom of conscience, religious tolerance, and the spirit of voluntary service.