Every other good marriage that we see is heterosexual. All the homosexuals are punished. The absence of the opposite proves this, kinda like gravity - sure, there's no way to prove it works 100% of the time, but we've never seen it do anything else.
You have yet to convince me why we should use the Bible as the standard from which to base our marriage laws.
Because we were founded on Biblical (not Christian, but Biblical) principles.
This is, of course, true. It's well known that the Constitution is lifted almost verbatim from Leviticus and the Bill of Rights simply paraphrases the Sermon on the Mount (blessed be those who bear arms; blessed by those who speaketh as they wish; etc...).
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