There have been letters to the editor where people have quoted the Bible to try to justify their point of view on a particular subject.
We need to remember that the Constitution, not the Bible, Quran or any other religious text, is the law of the land. The Constitution keeps the government from interfering with the practice of one's faith, but also protects anyone from having to conform to someone else's faith.
If individuals want to use a religious text to guide their personal life, I would strongly defend their right to practice that faith. I would just as strongly defend anyone from having to have someone's religious views or practices forced on them.
The only requirement for anyone to have the same rights and privileges as anyone else is the title of citizen, without regard to any other factor. In this country, we have no second-class citizens for any reason at all, and those would try to make any citizen have less than full citizenship rights are arrogant, discriminatory, and, most of all, un-American.
For the life of me, I do not understand the attraction two men have for one another, but as a straight male, I am not in the least threatened by gay marriage. It does not threaten my liberties or freedom in any way whatsoever.