At best, Jefferson was a deist. Had he lived in our time, I have no doubt he would be an atheist. Atheism in the 18th Century was not a safe philosophy. Many quotes from Jefferson suggest a secret atheism.
Question with boldness even the existence of a god; because if there be one he must approve of the homage of reason more than that of blindfolded fear. Letter to Peter Carr, August 10, 1787.
In every country and in every age, the priest has been hostile to liberty. He is always in alliance with the despot, abetting his abuses in return for protection to his own." Letter to Horatio G. Spafford, March 17, 1814.At the very least, Jefferson had nothing positive to say about Christianity.
Millions of innocent men, women and children, since the introduction of Christianity, have been burnt, tortured, fined and imprisoned; yet we have not advanced one inch towards uniformity. Notes on Virginia, 1782.
It is between fifty and sixty years since I read it (i.e. the Book of Revelations), and I then considered it merely the ravings of a maniac, no more worthy nor capable of explanation than the incoherence of our own nightly dreams. Letter to General Alexander Smyth, Jan. 17, 1825.
And the day will come when the mystical generation of Jesus, by the supreme being as his father in the womb of a virgin will be classed with the fable of the generation of Minerva in the brain of Jupiter. But may we hope that the dawn of reason and freedom of thought in these United States will do away with this artificial scaffolding, and restore to us the primitive and genuine doctrines of this most venerated reformer of human errors. Letter to John Adams, April 11, 1823.
The whole history of these books (i.e. the Gospels) is so defective and doubtful that it seems vain to attempt minute enquiry into it: and such tricks have been played with their text, and with the texts of other books relating to them, that we have a right, from that cause, to entertain much doubt what parts of them are genuine. Letter to John Adams, January 24, 1814.What would Jefferson think today about his image being used in connection with "In God We Trust?"