I'm not worried with "reconciling my position" with the Establishment clause, whatever that is. If it agrees, great, if it doesn't, just as good. Doesn't amount to a hill of beans, to me.
So, let's follow this reasoning:
The Divine law is the standard (which it is for me, as well. Let's assume, for now, that we're talking about the same Divine law, though I suspect you interpret it FAR differently than I do)
You say it's not right, according to the standard, to ensure that same-sex marriages aren't state-recognized b/c they don't correspond to my beliefs, which are governed by the Divine law, the very standard you say we're deviating from.
Therefore, we're NOT following the standard (the Divine law) b/c we are trying to ensure that things that run afoul of the standard (same-sex marriages) aren't legally recognized, which is wrong per the standard??
How does that work? I think what might need to be clarified is your position on how the "standard" governs same-sex marriages, and whether they're allowed or not.