They don't need to 'denounce' anything. They raise their hands to "preserve, protect and defend the Constitution of the U.S."

Religious tests for political office are proscribed IN that Constitution. Are you familiar with it?

Quote:

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The No Religious Test Clause of the United States Constitution is a clause within Article VI, Clause 3. By its plain terms, no federal office holder or employee can be required to adhere to or accept any particular religion or doctrine as a prerequisite to holding a federal office or a federal government job.

It immediately follows a clause requiring all federal and state officers to take an oath or affirmation to support the Constitution. This clause contains the only explicit reference to religion in the original seven articles of the U.S. Constitution.

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