aaah, thanks?

Back at ya...
Seriously though. Here is what the constitution says ~exclusively~ as far as religion is concerned. I can not find a single other mention:
"Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof..."
It's actually in the first ammendment to the Constitution.
To me that says no law can be passed which restricts (insert religious thing here) what-so-ever...
I realize that some where 'separation of church and state' became a familiar mantra, and suspect someone knows where it originated. Please enlighten.
I still thinks this mean that state stays out of church and church does what ever it wants.
I don't understand how it has EVER been interpretted otherwise.
ANY legislation or regulation from the government that SAYS anyone, anywhere, in any circumstance, can OR can't have or do ANY religious thing is unconstitutional.
I am trying to stay away from the merits or dangers of any specific religion. I'm not sure it's all that mundane. I am hoping to take this thread down the path of reasonable consitutional interpretation.
Comments,
-bear