Boston ? Let’s just say that the man selling newspapers at the entrance of the Government Center subway station hadn’t yet caught the spirit of the day. Marriage comes with three rings, he was telling a customer, “engagement ring, wedding ring, suffering.”

But the headline in the paper he was hawking had a different take on this historic moment. It announced simply: “FREE TO MARRY.”

Monday was the first day in which gay couples in Massachusetts could tie the legal knot. “Free to marry” may sound like a contradiction in terms — liberated to be committed? — but not among those lined up to get licenses.

Men and men, women and women formed an ad hoc reception line snaking out of Boston City Hall as the media walked up and down with pens and cameras.

Rebecca Priest and Madonna Berry wanted to tell me they had met through a newspaper personals ad eight years ago — “fortysomething, independent, loves the movies.”

Mark Strickland and Tread Pearson wanted to be sure that I knew they were being married by a Methodist minister.

Abha Agrawal and Vijay Sharina, a doctor and biologist, said they had come here a dozen years ago from India “to a place they could be together happily.”

Those I met had been together anywhere from one year to 18. Some shared houses. Others shared children. Most said they already felt married. Yet when the chance came to be married, it was different.

Janet Deegan and Constance Cervone, who share a mortgage and a real estate business and a 12-year relationship — how much more committed can you get? — shared something else: a case of the premarital jitters.

A decade ago, a few hamlets in liberal pockets of America tested out the idea of “domestic partnership.” When a gay couple in Hawaii sued for marriage, saying “we want the whole enchilada,” many gay rights leaders were leery of even putting marriage on the agenda. In 2000, the first civil unions were legalized in Vermont and the citizens reacted as if the sky were falling and the maple sap had stopped running.

Now after a historic court ruling, same-sex couples in Massachusetts are — for now at least — marriage material. As the stickers from GLAD, the Gay and Lesbian Advocates and Defenders, boasted: “We do the courting, you do the marrying.”

So put aside for a moment the controversy. Put aside the folks who believe that same-sex marriage will destroy traditional marriage. In their shared jitters, the couples “free to marry” in Massachusetts reinforce the power of a somewhat battered institution.

What seems so radical from a distance seems conservative when close-up and personal. Not just because we have extended old rights to a new category of citizens. Not just because the marriage debate has turned the face of gay America into an image of two dads, two moms, a kid, a golden retriever, and a soccer schedule.

It’s conservative because it presents and upholds marriage itself as the official gold standard of relationships, the socially accepted test of commitment that gay couples too now face.

Marriage in America has been sorely tested. Half of all marriages end in divorce. In 2000, 5.5 million unmarried couples lived together — and nearly 5 million of them were heterosexual. We’ve developed a whole in-between set of rights and benefits for the not-exactly-married.

As gay couples are allowed to legally wed, ironically, the line that separates marriage from partnership may be redefined. As marriage becomes possible, every gay couple will face “the conversation” common to straight couples: Where are we going? What does commitment mean? Is marriage the “whole enchilada”?

These couples want a license to join, not to destroy, marriage. Two by two, they are reminders of the importance of marriage as a passage, a public commitment and a support system. They are even reminders of the power of tradition.

At 9:30 Monday morning, a few subway stops away, up the tulle-wrapped staircase of Cambridge City Hall, I watched Tanya McCloskey and Marcia Kadish take each other “to be my spouse.” They promised “My friendship, my support and my love.”

Yes, these veterans of an 18-year-old relationship were already committed for better or for worse. Yet they too confessed to “shaking” before the justice of the peace. Just like newlyweds.

Meanwhile down in Provincetown, two men — one of them a divorce attorney — said they were getting married because, as one told a TV reporter, “I know one thing will be definite — it will be him.”

Engagement ring, wedding ring, suffering? There are few cynics applying for licenses in this wedding week. In Massachusetts, same sex couples are now choosing and celebrating the freedom … of commitment.

Ellen Goodman is a columnist for Washington Post Writers Group.