I was always fascinated by Jefferson's religious views, and how his lack of faith in the Christian God shaped his perspective on morality and liberty. The Jefferson Bible, formally known as The Life and Morals of Jesus of Nazareth, is a version of the Bible with most of the supernatural and spiritual elements removed. It offers an amazing insight into Jefferson's religious notions, and how he viewed the life of Jesus as noteworthy, but not divine.
Among his numerable quotes regarding religious belief, I find a paragraph regarding religion in a letter written to his nephew, Peter Carr, August 10, 1787, to be extremely enlightening:
Your reason is now mature enough to examine this object. In the first place, divest yourself of all bias in favor of novelty & singularity of opinion. Indulge them in any other subject rather than that of religion. It is too important, and the consequences of error may be too serious. On the other hand, shake off all the fears & servile prejudices, under which weak minds are servilely crouched. Fix reason firmly in her seat, and call to her tribunal every fact, every opinion. Question with boldness even the existence of a God; because, if there be one, he must more approve of the homage of reason, than that of blindfolded fear.
Jefferson encourages us to read the Bible as if it were a history from Tacitus or Livy, which I did myself during my sophomore year at UT. It's been a fascinating ride ever since.