It's hard to imagine someone I agree with more than Justice Black's opinions with respect to the Establishment Clause. His words in
Everson resonate strongly with me. While I do think some of his thoughts might have gone too far in some limited respects (I'm not against reasonable accommodations for those in the military or those in prison under the Free Exercise Clause), I couldn't put it better myself:
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.'
If the Establishment Clause meant only to cover actual establishment of state religion, it's effect would be almost without meaning. The First Amendment says that Congress (and through the 14th Amendment, the states) "shall make no law respecting an establishment of religion". Those words are broad in their meaning and intent. It should be given effect in the same way. I do not believe it requires full establishment of a religion to violate the Establishment Clause. Otherwise, it could allow for massive encroachments of religion into the state that reduces the Establishment Clause to an empty promise.