On your happy day you should be surrounded by people who can honor your vow and help you keep it. I can’t do that.
And on someone’s happy day, they don’t need to be preached at. Your smarmy stick-to-my-principles “talk” is, to my mind, just as bad as the little girl from Westboro Baptist Church telling an outsider, with a sickly-sweet smile on her face, “I’m sorry you’re going to hell.”
You, like many others, will decide what the Bible does and doesn’t say. You will, or will not, put words in mouths of saints, disciples and messiahs. And those words will be more about your own uninformed opinions than about the religion you claim to follow.
But when it comes to other peoples’ lives, those words don’t signify anything. Because other people don’t have the same beliefs as you. They have different faiths, principles, morals, etc. And morality is something a person chooses for themselves, not something imposed by someone else. When it comes to another person’s beliefs or values, I have bad news for you: You don’t get a vote. You never have and never will, and that’s not a state’s-rights issue.
I will refer you to what I call the First Rule of Other People’s Relationships: Keep your mouth shut.
The time to give your little speech is not after the happy couple has decided to have a wedding. It isn’t time when you get the invitation. It isn’t time during the tense hours right before the ceremony, at the reception, or even when the happy couple has returned from their honeymoon.
There are only two times when it is appropriate. The first is when one of them comes out as gay for the first time, or when you find out they’re gay. That’s the first and main time when it is appropriate for you to decide whether or not they are worthy of being in your halo-shrouded presence.
The other time is after the thank-you notes have been sent out.