“The executive power in our government is not the only, perhaps not even the principal, object of my solicitude. The tyranny of the legislature is really the danger most to be feared, and will continue to be so for many years to come. The tyranny of the executive power will come in its turn, but at a more distant period.” 

“...never [enter] into dispute or argument with another. I never saw an instance of one of two disputants convincing the other by argument. I have seen many, on their getting warm, becoming rude, & shooting one another. ... When I hear another express an opinion which is not mine, I say to myself, he has a right to his opinion, as I to mine; why should I question it? His error does me no injury, and shall I become a Don Quixote, to bring all men by force of argument to one opinion? ... There are two classes of disputants most frequently to be met with among us. The first is of young students, just entered the threshold of science, with a first view of its outlines, not yet filled up with the details & modifications which a further progress would bring to their knoledge. The other consists of the ill-tempered & rude men in society, who have taken up a passion for politics. ... Consider yourself, when with them, as among the patients of Bedlam, needing medical more than moral counsel. Be a listener only, keep within yourself, and endeavor to establish with yourself the habit of silence, especially on politics. In the fevered state of our country, no good can ever result from any attempt to set one of these fiery zealots to rights, either in fact or principle. They are determined as to the facts they will believe, and the opinions on which they will act. Get by them, therefore, as you would by an angry bull; it is not for a man of sense to dispute the road with such an animal.”

“With your talents and industry, with science, and that steadfast honesty, which eternally pursues right, regardless of consequences, you may promise yourself everything but health, without which there is no happiness.”

“I agree with yours of the 22d that a professorship of Theology should have no place in our institution. but we cannot always do what is absolutely best. those with whom we act, entertaining different views, have the power and the right of carrying them into practice. truth advances, & error recedes step by step only; and to do to our fellow-men the most good in our power, we must lead where we can, follow where we cannot, and still go with them, watching always the favorable moment for helping them to another step.

“If by religion we are to understand sectarian dogmas, in which no two of them agree, then your exclamation on that hypothesis is just, "that this would be the best of worlds if there were no religion in it.” 

“If once the people become inattentive to the public affairs, you and I, and Congress and Assemblies, Judges and Governors, shall all become wolves. It seems to be the law of our general nature, in spite of individual exceptions.” 

“If all be true that I do think, there are five reasons we should drink. Good friends, good times, or being dry, or lest we should be by and by, or any other reason why”

“If you want something you've never had You must be willing to do something you've never done.” 

“The truth is that the greatest enemies to the doctrines of Jesus are those calling themselves the expositors of them, who have perverted them for the structure of a system of fancy absolutely incomprehensible, and without any foundation in his genuine words. 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 we may hope that the dawn of reason and freedom of thought in these United States will do away with all this artificial scaffolding and restore to us the primitive and genuine doctrines of this, the most venerated reformer of human errors. -Thomas Jefferson to John Adams (April 11, 1823)” 

“If we could believe that he [Jesus] really countenanced the follies, the falsehoods, and the charlatanism which his biographers [Gospels] father on him, and admit the misconstructions, interpolations, and theorizations of the fathers of the early, and the fanatics of the latter ages, the conclusion would be irresistible by every sound mind that he was an impostor... We find in the writings of his biographers matter of two distinct descriptions. First, a groundwork of vulgar ignorance, of things impossible, of superstitions, fanaticisms and fabrications... That sect [Jews] had presented for the object of their worship, a being of terrific character, cruel, vindictive, capricious and unjust... Jesus had to walk on the perilous confines of reason and religion: and a step to right or left might place him within the gripe of the priests of the superstition, a blood thirsty race, as cruel and remorseless as the being whom they represented as the family God of Abraham, of Isaac and of Jacob, and the local God of Israel. They were constantly laying snares, too, to entangle him in the web of the law... That Jesus did not mean to impose himself on mankind as the son of God, physically speaking, I have been convinced by the writings of men more learned than myself in that lore.

“I am not a Federalist because I never submitted the whole system of my opinions to the creed of any party of men whatever....Such an addiction is the last degradation of a free and moral agent. If I could not go to heaven but with a party, I would not go there at all.”

“In questions of power, let no more be heard of confidence in man, but bind him down from mischief by the chains of the constitution.”

“Experience hath shewn, that even under the best forms, those entrusted with power have, in time, and by slow operations, perverted it into tyranny; and it is believed that the most effectual means of preventing this would be, to illuminate, as far as practicable, the minds of the people at large...”

“Whatever enables us to go to war, secures our peace”

“The art of life is the art of avoiding pain; and he is the best pilot, who steers clearest of the rocks and shoals with which it is beset.”