Warren Throckmorton, PhD is an Associate Professor of Psychology at Grove City College (Pa.). He blogs regularly about religious and mental health issues at www.wthrockmorton.com.

Earlier this month, the evangelical writer David Barton’s new book, “The Jefferson Lies,” hit the New York Times bestseller list for hardcover nonfiction. Barton isn’t popular, however, only with the ordinary American reader. On May 8, John Boehner authorized the use of Statuary Hall in the U.S. Capitol for a religious service to commemorate the first inauguration of George Washington. Among the speakers was Barton, who is revered by social conservatives because he argues that the nation was founded primarily by evangelical Christians on explicitly Christian teachings.

Barton — “one of the most important men alive,” according to Glenn Beck — is frequently criticized as a pseudo-historian by progressives and academic historians for his claims about the Founders. He is now facing scrutiny, however, from evangelicals. After Barton’s speech in the Capitol, John Fea, chairman of the history department at evangelical Messiah College, accused Barton of “peddling falsehoods” about Washington, and asked, “Is it time to gather Christian historians together to sign some kind of formal statement condemning Barton’s brand of propaganda and hagiography?”

There is no question that Barton’s history lessons are important to the conservative wing of the GOP. Barton, who was named one of Time magazine’s top 25 most influential evangelicals in 2005, was also tapped by Tea Party Caucus chairwoman Michele Bachmann to teach classes on the Constitution to congressional members in 2010....