Article 6 of the U.S. Constitution contains this provision:
The Senators and Representatives before mentioned, and the Members of the several State Legislatures, and all executive and judicial Officers, both of the United States and of the several States, shall be bound by Oath or Affirmation, to support this Constitution; but no religious test shall ever be required as a qualification to any office or public trust under the United States.
That prohibition on religious tests is clearly about actually holding an office after an election with a test imposed by the government. No person can be forced to swear allegiance to the Christian God or all the false gods out there as a condition to actually take a seat in office once elected or as a requirement to get their name on a a ballot.
That provision does not mean that you are forced to ignore someone’s religion or lack thereof. In the same way that some on the left will not vote for a Christian (religion test there), you do not have to vote for a Muslim.
Ben Carson was asked about this and he said he would not support a Muslim for President unless that person rejected sharia law.
Works for me. I agree with him. In fact, in order, I’d vote for a Christian or Jew before I’d vote for a Muslim and I’d vote for a Muslim before I’d vote for an atheist. World views matter. To me, faith matters. It may not matter to you, but it is dumb to say it violates the “religious test” clause. That’s simply not true.
Oh, and I suspect Ted Cruz did not know exactly what he was answering because he very clearly got wrong what he was applying to Ben Carson and I don’t know that it is smart for Cruz to be lecturing Carson when he won’t say one ill word about Donald Trump.