Ian Finkenbinder came to the steps of the Supreme Court wearing the dress uniform from the Army that discharged him after he said he was gay.

John Lewis and Stuart Gaffney donned the black tuxedos and bright blue ties they wore for their 2008 marriage in California.

Carmen Guzman came bearing tearful memories of a step-parent who called her a deviant when she came out, and high school classmates who sneaked up behind her and pushed her down the stairs.

“I have waited my entire life for this day,” said Guzman, of McLean, who arrived with her wife, Ikeita, outside the Supreme Court on the day it heard arguments in the first of two cases involving gay marriage.

Inside the court, the justices were grappling with often highly technical questions involving precedent and standing. But for many of the thousands who massed on the sidewalks and streets outside — some after waiting days to get a coveted seat inside — the issues were intensely personal.

On Tuesday, the Supreme Court took up the Proposition 8 case, the challenge to California’s ban on same-sex marriage. The Post’s Robert Barnes explains what you need to know from the hour of oral arguments. (JulieAnn McKellogg/The Washington Post)

“It’s our very lives that are before the court today,” said Gaffney, 50, recalling being introduced to Lewis at a party 26 years ago and thinking he had just met his future husband. “I wouldn’t want to be anywhere else in the world today. It’s history in the making.”

Many in the crowd played a role in making that history happen.

Jennifer Pizer and Jon Davidson of Lambda Legal, a gay activist group that brought a suit overturning laws that criminalized sodomy, got up at 4:30 a.m. to be near the front of the line for lawyers seeking seats inside the court.

“It’s a little scary,” she said of the uncertainty over how the court will rule. “But we all know we’re living in a very special moment.”

Finkenbinder, an Arab linguist from Seattle who was booted from the Army after announcing his sexual orientation, has become an activist who once chained himself to the White House fence to protest the administration’s now abandoned “don’t ask, don’t tell” policy.

Judging by the signs they carried, the crowd was overwhelmingly composed of people and groups that support marriage equality. Some had conversations, mostly civil, with people supporting the traditional definition of marriage.

“It’s been okay,” said Orlando Irizarry, a pastor from Providence, R.I., of the exchanges between marriage equality supporters and Irizarry’s group holding up a banner reading “Man + Woman = Marriage.”

“What is so beautiful about this nation is you can give your point of view in peace.”

Eight members of the Topeka-based Westboro Baptist Church, who often demonstrate at military funerals, held provocatively worded signs indicating their view that God does not confer grace on homosexuals.

Staking out a position right next to them were several members of Ravensworth Baptist Church in Annandale, which is part of the Association of Welcoming and Affirming Baptists. Before going to the court, they had attended an interfaith service of other religious people who also support same-sex marriage.

“I kept thinking of Martin Luther King standing before that other courthouse in Montgomery,” said Steve Hyde, the Ravensworth pastor. “That’s where he said: ‘How long? Not long.’ I sense something is happening today. It’s a great day to be on the right side of history.”

Others also saw similarities with the civil rights movement. Melissa Wasser, 26, came with several friends from Youngstown State University in Ohio, where she is a junior. She carried a handmade poster that included a wedding portrait of her African American father and white mother.

“My parents used to be illegal, too,” the poster said.

Some tourists, unable to resist the allure of being in town while a potentially landmark case was before the court, rose early to join long lines hoping for coveted seats inside.

Melissa Leathers drove into Washington from Cincinnati on Monday night, planning to show her children the city’s monuments during spring break. But her son, Will, who dreams of becoming a lawyer, helped persuade her to make the Supreme Court their first stop.

“My son turns 18 next week, and all he wanted for his birthday was to get a seat in court so he can hear arguments,” she said.

Afia Bonner and Michele Didero flew in from San Francisco. They voted against Proposition 8, the voter-approved gay marriage ban now before the court, and they wanted to see how it ends, like the last chapter in a book.

But however the judges rule, the young women, both in their early 20s, said they are mindful of how much older gay activists have had to fight and how rapidly American attitudes toward same-sex couples have shifted.

“We started on second base,” said Bonner, who is 23. “It’s sad to think we have to keep on fighting. But every generation has its own battles.”