MARRIAGE IS A sacrament. A function of the church, not the state.

Given all that we are up against today, the state should not perform "marriages" for anyone. Only religious institutions should do that. The state should offer civil unions for anyone. I'll explain the italics later.

With President Obama's "evolution" returning gay marriage to Page One, I remain conflicted: emotionally in favor of it, but intellectually opposed. I strongly endorse civil unions, with the stipulation that persons in such a union have precisely the same rights as a married couple. No difference.

But there is a difference, I am told by Malcolm Lazin, executive director of the Equality Forum.

"The federal government provides 1,138 federal marital protections and benefits currently being denied under the Defense of Marriage Act," he says.

That is wrong, should be corrected and must be corrected. I believe in equality of treatment, not of language.

When Obama dropped the seventh veil and announced he favored gay marriage, he gave a great lift to American gays because he was the first president to do so. Lazin equates it with President Truman's righteous order to desegregate the military and President Johnson's overdue ramrodding of the 1965 Civil Rights Act. Obama took his position with some, but not much, political risk.

It was an expression of "human and civil rights," according to many, including the Rev. Al Sharpton, who said Obama did not do it to gain votes in the LGBT community. They are deeper in his pocket than lint, so maybe Sharpton's right. He had their support (and their money) anyway. Lazin says Obama captured 75 percent of the LGBT vote against John McCain and will probably do at least as well against Mitt Romney, and the president's stand assures that those wallets will be wide open.

A majority of his firmest base, African-Americans, opposes gay marriage but nothing he says or does will prevent him from getting about 94 percent of that vote.

Although public-opinion polls show Americans nearly equally divided on gay marriage, it has failed every time it has been put to a statewide referendum.

Most Democrats favor it, nearly all Republicans oppose it, but those are numbers, not reasons. Obama's pro-gay-marriage stand will not shift many votes in those camps.

Where might it? Among independents. He could shift a few percentage points there. Among strong Christians (and Orthodox Jews and fundamental Muslims) his declaration could cost him votes.

So why do I oppose "same-sex marriage," which is framed as "marriage equity"? Because you can achieve "equity" absent the M-word.

Using the M-word is offensive to the religiously observant, and their feelings need to be considered, too. To them, it is a deliberate thumb in the eye — and remember, it is their word. To some gays, the M-word is a necessity; to a lesser number, a "trophy."

Finally, if we change the millennia-old practice of defining marriage as one man and one woman, there will be unintended consequences.

If we don't have to stick to the gender in "one man and one woman," why do we have to cleave to the number mentioned? How can we deny polygamy and polyandry to those who define the practices as part of their "human and civil rights"?

When I try that argument on my gay friends, most say it is "silly" and "won't happen."

Lazin says it's the argument lofted by the far right, the courts won't permit it and it is historically flawed because the Bible mentions polygamy without condemnation.

I don't care which end of the spectrum an argument comes from. I examine everything on its own merits.

I guarantee you that 30 years ago the idea even of gay civil unions would have been remarkable if not preposterous. I fear that "same-sex marriage" will open a door to other practices I don't want to see in America.

Email stubyko@phillynews.com or call 215-854-5977. Join Stu on Facebook. For recent columns: www.philly.com/Byko.