"Of all the dispositions and habits which lead to political prosperity, religion and morality are indispensable supports. . . . And let us with caution indulge the supposition that morality can be maintained without religion. Whatever may be conceded to the influence of refined education on minds of peculiar structure, reason and experience both forbid us to expect that national morality can prevail in exclusion of religious principle."
- George Washington, 1796²⁴

"As the Government of the United States of America is not, in any sense, founded on the Christian religion; as it has in itself no character of enmity against the laws, religion, or tranquillity, of Mussulmen; and, as the said States never entered into any war, or act of hostility against any Mahometan nation, it is declared by the parties, that no pretext arising from religious opinions, shall ever produce an interruption of the harmony existing between the two countries."
- Treaty of Tripoli, 1797²⁵

"Believing with you that religion is a matter which lies solely between Man & his God, that he owes account to none other for his faith or his worship, that the legitimate powers of government reach actions only, & not opinions, I contemplate with sovereign reverence that act of the whole American people which declared that their legislature should 'make no law respecting an establishment of religion, or prohibiting the free exercise thereof,’ thus building a wall of separation between Church & State."
- Thomas Jefferson, 1802²⁶

"Probably, at the time of the adoption of the constitution and of the amendment to it, now under consideration, the general, if not the universal, sentiment in America was, that Christianity ought to receive encouragement from the state, so far as was not incompatible with the private rights of conscience, and the freedom of religious worship. An attempt to level all religions, and to make it a matter of state policy to hold all in utter indifference, would have created universal disapprobation, if not universal indignation."
- United States Supreme Court Justice Joseph Story, 1833²⁷

"The 'establishment of religion’ clause of the First Amendment means at least this: Neither a state nor the Federal Government can set up a church. Neither can pass laws which aid one religion, aid all religions, or prefer one religion over another. Neither can force nor influence a person to go to or to remain away from church against his will or force him to profess a belief or disbelief in any religion. No person can be punished for entertaining or professing religious beliefs or disbeliefs, for church attendance or non—attendance. No tax in any amount, large or small, can be levied to support any religious activities or institutions, whatever they may be called, or whatever form they may adopt to teach or practice religion. Neither a state nor the Federal Government can, openly or secretly, participate in the affairs of any religious organizations or groups and vice versa. In the words of Jefferson, the clause against establishment of religion by law was intended to erect 'a wall of separation between church and State."
- United States Supreme Court, 1947²⁸

"Our government makes no sense unless it is founded on a deeply held religious belief—and I don’t care what it is."
- President Dwight Eisenhower²⁹

"It is a profound religious message, but it’s a profound religious message believed in by the vast majority of the American people, just as belief in monotheism is shared by a vast majority of the American people. And our traditions show that there is nothing wrong with the government reflecting that. I mean, we’re a tolerant society religiously, but just as the majority has to be tolerant of minority views in matters of religion, it seems to me the minority has to be tolerant of the majority’s ability to express its belief that government comes from God, which is what this is about."
- Supreme Court Justice Antonin Scalia, referring to the six-foot monolith inscribed with the Ten Commandments displayed on the grounds of the Texas state capitol, 2005³⁰

"I'm completely in favor of the separation of Church and State. My idea is that these two institutions screw us up enough on their own, so both of them together is certain death."
- Comedian George Carlin³¹