The separation of church and state is the founding principle in the protection of religious freedom as provided in the First Amendment to the Constitution; and, moreover, the Supreme Court has so interpreted the Constitution. In Everson v. Board of Education, the Supreme Court ruled:
"The meaning and scope of the First Amendment, preventing establishment of religion or prohibiting the free exercise thereof, in the light of its history and the evils it was designed forever to suppress, have been several times elaborated by the decisions of this Court prior to the application of the First Amendment to the states by the Fourteenth. The broad meaning given the Amendment by these earlier cases has been accepted by this Court in its decisions concerning an individual's religious freedom rendered since the Fourteenth Amendment was interpreted to make the prohibitions of the First applicable to state action abridging religious freedom. There is every reason to give the same application and broad interpretation to the 'establishment of religion' clause. The interrelation of these complementary clauses was well summarized in a statement of the Court of Appeals of South Carolina, quoted with approval by this Court, in Watson v. Jones, 13 Wall. 679, 730: 'The structure of our government has, for the preservation of civil liberty, rescued the temporal institutions from religious interference. On the other hand, it has secured religious liberty from the invasions of the civil authority.'
"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 from 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.' Reynolds v. United States, supra, 98 U.S. at page 164." [footnotes omitted] Everson v. Board of Education of Ewing TP. et al., 330 U.S. 1, pp. 15,16 (1947).