For many people today, it's a controversial question. But not for the nation's founders who saw the Bible as the basis for the American Revolution.
The men who fought a revolution and created a country -- the most free country to have ever existed -- once gathered in the Independence Hall in Philadelphia.
Why so much freedom? Some say because the revolutionaries accepted what the Bible said about human beings, that they are created in the image and likeness of God.
"(It was the first time in history) an entire country was actually founded upon the idea that all human beings possess certain innate inalienable natural rights," Robert Hutchinson, author of The Politically Incorrect Guide to the Bible, said. "And that these are not privileges that are bestowed by the state, but are gifts from God that no state, no king or potentate can take away."
So what did the men who gathered in the hall believe?
Some modern scholars would have you think if the founding fathers did believe in a God, he was removed from the affairs of humanity. But others indicate they believed in the God of the Bible -- an intimate Lord who bestowed upon them blessings, and gave them both responsibilities and rights.
Pastor Peter Lillback authored the book Wall of Misconception in part to correct misunderstandings about the founders and their faith.
"There are those who would like to argue that we were started by secularists, those who had no interest in religion," he said. "At best they were deists: that God was irrelevant. And the deists said 'God has not spoken.' There is no Word of God for a deist because God is not involved in history."
And yet the Bible is the book the revolutionaries turned to over and over again when laying the foundations for this country.
"Over one-third of the citations of our founders come directly from the Scriptures, more than any other book," Lillback continued. "They were not biblically ignorant. As one writer said, 'They knew the Bible right down to their fingertips.'"
Another third of the founders' citations came from masters of philosophy and law, who just happened to be Christians who drew deeply from the Bible.
"John Locke, Montesquieu, and Blackstone - all of them were Christian thinkers. And that's two-thirds of our founders' writings by explicitly Christian thinkers and the Bible," Lillback said.
Interestingly, the founding fathers didn't feel it was simply their right to overthrow their British rulers, but a biblical responsibility.
"There are clear passages in the Bible that when a ruler becomes a tyrant it is the duty of the people to overthrow him because he ceases to be a legitimate leader and is now a criminal," Hutchinson explained.
Two of the most famous founders felt so deeply about this idea, they thought it should become America's motto.
"Thomas Jefferson and Benjamin Franklin both wanted to have the motto 'Rebellion to Tyrants is Obedience to God.' That's actually a very biblical idea," the author continued.
Church and State
Some scholars say these founders wanted a high wall of separation between church and state, and infer that this meant they wanted a vast distance between God and government.
"It's absolutely clear our founders did not want to separate God and government," Lillback claimed. "The Declaration of Independence on four occasions refers to God and that created our government."
"The last words in the United States Constitution say 'in the year of our Lord 1787.' Every preamble of every state constitution begins with an affirmation of the existence of God," he added.
Lillback explained that the wall the founders built with the First Amendment was to prevent America establishing a coercive state church like so many other countries. It wasn't to separate God and government.
"It was rather, 'We don't want the government to tell us how to interpret the Bible and how to use the Bible in our worship. We want to be protected from government coercion,'" he said.
The very fact the founders created a democratic republic is because of their biblical beliefs.
"Ancient Israelites were basically a tribal democracy and in Deuteronomy God commands that the people select leaders from all the people," Hutchinson said.
Representing the People
The founders who gathered at Independence Hall time and again spoke of how they felt God expected them to forge a form of government that could best guard the rights He gave human beings. They searched diligently in the writings of top Christian philosophers for the best ideas.
"The Catholic theologian Thomas Aquinas thought that the ideal form of government was a mixed government that had elements of a democracy, an aristocracy, and a kingship," Hutchinson continued.
That's remarkably similar to what our founders created: a Congress to represent the people, a judiciary to judge their laws, and an executive to execute those laws.
The arrangement was all meant to give the maximum amount of liberty to a free people and to protect their God-given rights.
"If you don't believe that human rights are something given by God, then they can be taken away at the whim of the state," Hutchinson said. "And we've seen that time and again when atheistic regimes have taken over."
When a citizen who met Ben Franklin outside Independence Hall asked what he and the other founders had created inside, he said, "A republic, if you can keep it."
President John Adams warned..."Our constitution was made only for a moral and religious people."
In other words, only in a land where citizens believe God made men free will freedom long survive.
As Patrick Henry put it, "It is when a people forget God that tyrants forge their chains."
Hutchinson says this holds true with few exceptions.
"The only countries on earth that actually practice religious tolerance and have civil liberties and political freedoms are those nations that descended from the biblical heritage," he said.
Many scholars agree that it matters whether or not the founding fathers were true Christian believers. If they weren't, how could they have formed a Christian nation?
And that's a crucial question of national identity.
*Original broadcast July 4, 2009.