Jefferson, Neither Atheist Nor Outlier:

Regarding Christopher Hitchens' assertion, I don't see anything in the historical record to indicate Thomas Jefferson was an atheist. The Straussian argument for Jefferson's atheism -- that he had to publicly proclaim belief in God, else his reputation be ruined, but didn't really believe it -- is, as Ed Brayton notes, contradicted by the fact that Jefferson claimed to firmly believe in God even in his private letters which contain the harshest anti-clerical rants, rants which, if publicly known, would have ruined his reputation.

I disagree with Sandefur that Jefferson may have written in code in his private letters to John Adams. I interpret their correspondence as showing that the two were almost entirely agreed on their personal religious creed. Call it "unitarianism," call it "theistic rationalism," you could even call them "Priestlians" because Joseph Priestly -- the discoverer of oxygen -- was probably the most important influence on both Adams' and Jefferson's (and other key Founders') religious beliefs. Both Adams and Jefferson (and Franklin) commonly referred to "the corruptions of Christianity." Priestly coined that phrase and it had very specific meaning. Priestly wrote a book entitled A History of the Corruptions of Christianity which caused masses of Trinitarian Christians to burn his house down in England, where he then fled to America for refuge.

Priestly was thought to be so "notorious" as deserving to have his house burned because the "corruptions of Christianity" turned out to be the heart and soul of orthodox Christian doctrine: "a trinity of persons in the godhead, original sin, arbitrary predestination, atonement for the sins of men by the death of Christ, and ... the doctrine of the plenary inspiration of the scriptures." (That quotation by the way, is sourced by both Gregg Frazer and Brooke Allen). So when Jefferson, Adams and Franklin referred to the "corruptions of Christianity" -- as they often did -- they signified they disbelieved these doctrines central to Christianity. Both Jefferson and Adams, let's not forget, called themselves "Christian." But this is not unlike Mormons calling themselves Christian, and then explaining, "but here is what we believe...," and upon hearing the details, evangelical Protestants and Catholics react, "no, you aren't Christians."

Finally, while it may be true that Jefferson (and Madison) were outliers in the way they desired Church and State to be separate, Jefferson was not an outlier regarding his personal religious beliefs. Jefferson, Adams, Franklin, Madison, Washington, Wilson, G. Morris, and Hamilton (before his end of life conversion to orthodox Christianity) were all likely agreed on the central tenets of their personal religious beliefs.

Update: Before any of you call me on this, many websites state that whereas Priestly's book, "A History of the Corruptions of Christianity," was official burned in 1785, his house and church were burned in 1791 because of his support for the American and French Revolutions.