And what of it? Reasonable people do tend to come to that conclusion and have for over 2 thousand years.
Well, if Matthew Vines says it . . .
So wrong it ain’t even funny. The government defines “civil marriage” which is the legal relationship two people (formerly of the opposite sex in the USA) entered into voluntarily. It was defined by state legislatures until relatively recently when the Supreme Court decided that James Madison and Alexander Hamilton believed in a right to same-sex marriage and wrote that into the Constitution but were too drunk or stupid to tell anyone about it.
Yet, the Church (and I mean any of the churches) and even non-Christian religions have had their own canonical and theological definitions of marriage from before the modern iteration of “gubment” was even thought of.
Quite frankly the Establishment Clause of the 1st Amendment in the Bill of Rights prevents Congress from making any law respecting an establishment of religion or prohibiting the free exercise thereof. The states were incorporated into this provision by the 14th Amendment to the Constitution. So now neither Congress nor the 50 state legislatures can create laws respecting an establishment of religion or prohibit the free exercise thereof.
Therefore, churches can define marriage however they like and neither you nor Congress nor the Supreme Court can tell any religious group “what marriage is.” Before you reference “separation of church and state,” you might want to actually learn what that means.
For purposes of this conversation, it means that yes churches do have the right to “define what marriage is.”
(As does each individual, by the way, since this is, you know, supposed to be a “free country.”

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