Legal Advice If You Want To Make Us A Theocracy.

"BLASHPHEMY at common law, the misdemeanor of reviling and ridiculing the established religion [Christianity] and the existence of God."

Law Dictionary by Steven H. Gifis, Barron's Legal Guides.

So to do that, establish a theocracy here, you have to establish some specific church (not just "Christianity", he means the Anglican Church above). That is forbidden under the Establishment Clause, at the federal level. (Thomas says still it's okay on the state level though.) So you do away with the first clause of the First Amendment.

Of course having another constitutional convention could make the Judeo-Christian Bible the law of the land. You could also appoint SCOTUS judges who think the Bible already is. But they would have to be very, very uneducated, and do things like write legal opinions in green crayon, always green they'd tell people. So that last one might work. I don't know though.