Hogwash. There is no moral equivalence.
1. The unalterable religious historical truth you are referring to called holy matrimony.
2. Then later they sign a contract to form a civil union recognized by the state. This civil union is called a marriage license.
I would argue that government has no right at ANY level, local, state, or federal to interfere with #1.
And that #2 should be left up to the states.