“As I conceive this doctrine to be a gross misrepresentation of the character and moral government of God, and to affect many other articles in the scheme of Christianity, greatly disfiguring and depraving it; I shall show, in a fuller manner than I mean to do with respect to any other corruption of Christianity, that it has no countenance whatever in reason, or the Scriptures; and, therefore, that the whole doctrine of atonement, with every modification of it, has been a departure from the primitive and genuine doctrine of Christianity.”

Letter to Benjamin Rush (12 April 1803) https://founders.archives.gov/documents/Jefferson/01-40-02-0178-0001
1800s, First Presidential Administration (1801–1805)

General Conclusions, Part I : Containing Considerations addressed to Unbelievers and especially to Mr. Gibbon
An History of the Corruptions of Christianity (1782)

§ 232
The Reasonableness of Christianity (1695)

Some Reasons Why (1881)

Letter to James Smith (1822)
1820s
Context: No historical fact is better established, than that the doctrine of one God, pure and uncompounded, was that of the early ages of Christianity … Nor was the unity of the Supreme Being ousted from the Christian creed by the force of reason, but by the sword of civil government, wielded at the will of the fanatic Athanasius. The hocus-pocus phantasm of a God like another Cerberus, with one body and three heads, had its birth and growth in the blood of thousands of martyrs … The Athanasian paradox that one is three, and three but one, is so incomprehensible to the human mind, that no candid man can say he has any idea of it, and how can he believe what presents no idea? He who thinks he does, only deceives himself. He proves, also, that man, once surrendering his reason, has no remaining guard against absurdities the most monstrous, and like a ship without rudder, is the sport of every wind. With such person, gullibility which they call faith, takes the helm from the hand of reason, and the mind becomes a wreck.

Letter to Judge J. A. Wakefield, after the death of Lincoln's son Willie in 1862, as cited in Abraham Lincoln: was he a Christian? (1893), p. 292 http://books.google.com/books?id=x8BHAAAAIAAJ&pg=PA292&dq=%22unsoundness+of+the+Christian+scheme%22, by John Eleazer Remsburg. Historian Merrill Daniel Peterson states in Lincoln in American Memory (1994), p. 227 http://books.google.com/books?id=D_FjY_ARcGoC&lpg=PA227&vq=%22Judge%20J.%20A.%20Wakefield%22&pg=PA227, that the letter has never actually been produced to verify the statement and that there's no correspondence with Wakefield noted in the Collected Works.
Misattributed

On how she felt that her early roles were a form of liberation in “Body of Work: Screen Siren Raquel Welch Gets Her Lincoln Center Retrospective” https://observer.com/2012/02/body-of-work-screen-siren-raquel-welch-gets-her-lincoln-center-retrospective/ in The Observer (2012 Feb 7)

Source: Dictionary of Burning Words of Brilliant Writers (1895), P. 132.

"The Brooklyn Divines." Brooklyn Union (Brooklyn, NY), 1883.