You’ll search in vain to find a reference in the Constitution to the “wall of separation” between church and state.

Many students of American history know that the phrase originated with Thomas Jefferson, in a private letter sent during his first term as president.

Stephen Mansfield examines the history of the “wall” in Ten Tortured Words (Thomas Nelson, 2007). Mansfield notes that U.S. Supreme Court Justice Hugo Black built the wall into constitutional law in his 1947 decision, Everson v. Board of Education. Because no previous high court had ever treated the “wall” as law, “it quickly became obvious that a gap existed between the law and the practice of a century and a half. How was this gap to be closed?”

Neither the federal government nor the states maintained a special “religious police” force. Because traditional law enforcement officers had better things to do than ferret out religion in the public square:

The answer appeared almost immediately after the Court’s ruling. The enforcement would come from private organizations determined to search out and destroy, through litigation, any connection between government and religion. These groups became, in effect, Everson‘s private army, and their impact on the role of religion in America would prove transforming.

The book is a little short for its price tag. And it includes some historical errors that are difficult to ignore; for example, Mansfield implies that the framers of the U.S. Constitution wrote the 1787 Northwest Ordinance.

But those interested in the history of constitutional law and the popular understanding of the First Amendment might find Mansfields work useful.