But, if people want to say we are a Christian nation and want the ten commandments posted at the courthouse...[/'quote]
Historically, Baptists would disagree with both of those positions. Only in recent years have Baptists jumped on the "Christian nation" bandwagon - completely ignoring the Baptist witness of the last 500 years.
...then it shouldn't be acceptable period if there are biblical instructions on the subject, shouldn't matter whose property it's on whether church or government. If anything, the fact that it is on government property and not private property of a third party group should be more troubling to the Christian nation crowd but it isn't.
I'm not too concerned about the "Christian nation" crowd. They have other, more important issues to sort out. They also might know more about both the original Parthenon and the replica than you might imagine.
In regard to whether or not the replica violates the Baptist doctrine and the Constitutional principle of separation of church and state, the most used test by the Supreme Court, and lower courts, is the three-pronged “Lemon test” that was formulated in the Supreme Court decision,
Lemon v. Kurtzman (1971).
"First, the statute must have a secular legislative purpose…"
The purpose of the Parthenon replica was to showcase classic Greek architecture and as a curiosity for the Tennessee Centennial Exposition in 1897. Nashville was nicknamed, “The Athens of the South” and the City wanted to enhance that reputation with a recreation of the most famous architectural icon in Athens, even Greece.
The building was built without the statue of Athena (added in 1990) and the building came to be used as an art museum. While the building is authentic in scale - and now includes a recreation of the goddess Athena - the purpose is to be a historic homage. As a teenager, I visited the Parthenon in the late 1970s and was impressed with the scale of the building. It served as an education in ancient Western architecture, just as it was intended.
I think it is important to note that even the original Parthenon was not built as a place of worship. Only later did a cult of Athena develop. Originally, it was built as a symbol of civic pride by the people of Athens.
In my opinion, both the original and the current Parthenon pass this facet of the test.
"...second, its principal or primary effect must be one that neither advances nor inhibits religion..."
Unless I have completely missed something, there is no cult of Athena worshipping at the Parthenon. There are no priestesses, no offerings, no sacred owls, no incense, no appeals to Athena, etc.
The cult of Athena (if it even exists in modern form in Tennessee), is not aided or restricted by the existence of the replica.
In my opinion, it easily passes the second facet of the test.
"...finally, the statute must not foster "an excessive government entanglement with religion."
Since there is likely no cult of Athena operating in the US, there is no entanglement. The replica simply was not built for worship and there has been no entanglement.
In my opinion, it easily passes the third facet of the test.
In my opinion, according to the most widely-accepted legal test for church-state separation, the Parthenon replica is not a violation.