Due to the passage of time and changing customs in the nation, many have come to regard the first amendment guaranteeing religious freedom to be ambiguous
I think it is pretty straight forward and unambiguous.
the question whether the amendment specifically applied to the various denominations of Christianity extant at the time of writing or was meant to be extended to cover other religions
Being that Jews and synagogues existed from the very beginning of the fledgling nation, it would certainly seem to extend to the government simply taking a neutral position on religion.
It is true the verbiage from Thomas Jefferson concerning a wall of separation was written to the Danbury Baptists, which whom were concerned that the gov't would institute an offical state religion. He quelled their fears by assuring them there would be no state religion.
But, of course, there could have been no forseeable way the framers could have known about Wiccans being that Wicca was invented in the 1950's. But the spirit of the writing remains intact, and that is that the U.S. government will pass no law giving preference to a religion or an official endorsement.
"Political correctness is tyranny with manners." -- Charlton Heston
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