Senate candidate Christine O'Donnell asked, "Where in the Constitution is the separation of church and state?" during a debate against opponent Chris Coons, as he was making an argument about the teaching of religious ideas in public schools.
Turns out, the idea of "separation of church and state" is not spelled out in the Constitution, nor in the Declaration of Independence.
In fact it's never spelled out. It is implied by the First Amendment to the Constitution (part of the Bill of Rights, established in 1791):
"Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances."
Thomas Jefferson often gets a lot of credit for the thinking that preceded the First Amendment's freedom of religion wording. But the concept might never have come about if a radical immigrant named Roger Williams hadn't argued for it. Very persistently.
"Forced worship stinks in God's nostrils," Williams once said.
During the 17th century, many people left England to escape religious persecution. Many colonists came to America to be able to freely practice their religions. Williams, who was a defender of religious liberty, arrived in Boston on Feb. 5, 1631.
Ordained to the ministry in the Church of England, Williams discovered Puritanism, a reform movement that developed within the Church of England, during his first parish duty. He converted. Soon after, he was asked to be minister in the Massachusetts Bay Colony, according to an account by the Library of Congress. Leaving behind the religious intolerance under England's King Charles I, he and his wife journeyed across the ocean to join the "American Experiment" in Boston in 1631.
At first, Williams just wanted to reform the Church of England; soon, he sought separation completely.
Many of Williams' parishioners did not agree with his idea to separate from the Church of England. He then became minister in Salem. There, his ideas also proved too radical. He went to Plymouth but again fell into disfavor. Williams insisted that land must be purchased from the Indians, rather than taken from them forcefully, in order to claim title to it. He again went to Salem and was eventually put on trial in 1635 for his views. His sentence was banishment. Williams then purchased land from the Narragansett Indians and established the settlement of Providence, R.I.
Williams founded the colony of Rhode Island based upon principles of complete religious toleration, separation of church and state, and political democracy (values the U.S. would later be founded upon). It became a refuge for people persecuted for their religious beliefs.
Quakers, Jews and other religious groups settled in Rhode Island.
After forming the first Baptist church in America, Williams left it to seek spirituality in different ways. He stopped preaching to his friends, the native Americans, when he realized that their form of worship also fell under his principle of religious freedom.
This article was provided by Life's Little Mysteries, a sister site to LiveScience.
Live Science newsletter
Stay up to date on the latest science news by signing up for our Essentials newsletter.