Doesn't say that at all. All it says is that no one (of the Christian churches) ie Catholic, protestant, Anglican, will have favor over the other. It's freedom OF religion, not FROM religion. And government will not interfere with the church.
Doesn't say your take on it either; simply says that Congress can't make any law favoring or disparaging any religion. SO, if I want to worship a golden calf, Congress can't encourage it nor can Congress deny my right to do so. Thus the original statement stands.
"Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof." i.e. Congress will not establish a national religion, nor will they prevent any religion from practicing.