In a tribute that reiterated the degree to which the noble melodrama of Dr. Betty Shabazz's life and death touched so many people, thousands of mourners filled Riverside Church in Manhattan yesterday, with hundreds more spilling onto the sidewalks, to remember her as a brave widow, a loving mother and a tireless advocate for the oppressed.

The memorial, which followed Dr. Shabazz's private Muslim funeral on Friday, drew an eclectic assemblage of legislators, writers, ministers and entertainers.

There were brief testimonials about Dr. Shabazz, the widow of Malcolm X, not only from the current Mayor of New York City, Rudolph W. Giuliani, but from three of his predecessors: David N. Dinkins, Edward I. Koch and Abraham D. Beame. Gov. George E. Pataki spoke, as did Representative Maxine Waters, chairwoman of the Congressional Black Caucus.

The Secretary of Labor, Alexis Herman, came on behalf of the Clinton Administration, reading a letter from the President that called Dr. Shabazz ''a true heroine, a fine role model and a valued friend.''

And Myrlie Evers-Williams, the widow of Medgar Evers, sobbed and leaned into Coretta Scott King, the widow of the Rev. Dr. Martin Luther King Jr., as she described Dr. Shabazz as the third member of their sisterhood of sorrow, all of them having lost husbands whose blunt attacks on racial injustice courted grave personal danger.

Mrs. King, in turn, said, ''We married their mission, and that became our mission when they were no longer there.''

But perhaps the most emotional moment came when the oldest of Dr. Shabazz's daughters spoke of the family's heartache. The six women had maintained an almost uninterrupted public silence since Dr. Shabazz was critically injured on June 1, in a fire that the police say was set by her 12-year-old grandson, Malcolm Shabazz.

Her daughter Attallah Shabazz stood tall in a lofty pulpit carved from gray stone and recalled the slow, tense passing of the 23 days that Dr. Shabazz spent in the burn unit of Jacobi Medical Center in the Bronx, with her daughters close by.

''We tried to breathe life and hope into our mother,'' Ms. Shabazz said. ''We'd whisper in her ear, 'You don't have to fight so hard, Mama. We're doing it.' ''

Then, referring to the jeers that greeted Mayor Giuliani when he ascended the pulpit, Attallah Shabazz said her mother was always surrounded by peacemakers and tolerant of diversity, ''as opposed to those who boo when someone stands here to give a tribute to her. Can't happen.''

The turnout yesterday, in its size and wealth of dignitaries, demonstrated anew how Dr. Shabazz's struggle and violent end became, for many African-Americans, a universal allegory of aspirations, perseverance, bitter disappointments and uncontrollable twists of fate.

It also showed how Dr. Shabazz, as the widow of Malcolm X and the stubborn guardian of his legacy, had attained a place among modern African-American trailblazers.

The poet Haki Madhubuti said, in one of more than two dozen speeches from the pulpit, that the Shabazz, Evers and King families were ''First Families'' for African-Americans, with narratives that have become both public and symbolic.

Those narratives spanned decades of enormous change, several speakers said, noting that one of New York City's grandest cathedrals opened its doors yesterday for Dr. Shabazz.

''It is a far cry from 32 years ago, when no religious institution except one was willing to open its doors to the man called Malcolm X,'' said Percy Sutton, a lawyer and close friend of the Shabazz family who presided over the ceremony.

A dense line of people, most of whom had never known Dr. Shabazz, began to form outside Riverside Church four hours before the 3 P.M. service. By 2:30 P.M., the line was several blocks long, and only a fraction of the people in it could be accommodated with seats among the thousands in the main sanctuary.

An additional 600 mourners watched the service on closed-circuit television from a room in the church building. But that still left an overflow crowd on the sidewalk, listening to the speeches on a loudspeaker.

Inside, the music and the speakers reflected the diversity that Dr. Shabazz was said to treasure, the confluence of cultures she worked to achieve. The ceremony opened with African drumming and chants, and later paused for a rendition, by the Boys Choir of Harlem, of the pop song ''Wind Beneath My Wings.''

And there were prayers both Christian and Islamic: at one point, the Rev. James Alexander Forbes Jr. of the Riverside Church stood in a pulpit on the left, while Imam Al-Hajj Talib Abdur-Rashid of the Mosque of Islamic Brotherhood stood in a pulpit on the right.

Many of the faces in the pews were instantly recognizable, from Marion Barry, the Mayor of Washington, to the actor Edward James Olmos. Maxine Waters was accompanied by at least three other Congressional representatives: Eleanor Holmes Norton, Charles B. Rangel and Carolyn B. Maloney.

Ossie Davis and Ruby Dee delivered the formal eulogy, and their words, like those of many speakers, seemed as much about the history of black Americans as the history of Dr. Shabazz.

''We've been to hell and back again,'' said Mr. Davis, who also spoke at Malcolm X's funeral. ''And death cannot have the final word. We've been black too long to grant him that.''

Others focused more specifically on Dr. Shabazz, praising her as a survivor who raised six daughters by herself and still found the time to study for a doctorate in education.

She was selfless, they said, in satisfying countless requests to speak at public events, about her visions for the country as well as her dead husband's.

They recalled that she cared deeply about other people's children, spending the last two decades as an administrator at Medgar Evers College in Brooklyn. And they recalled that she cared deeply about her own daughters.

Looking out at the front middle pew, where those daughters sat, the poet Maya Angelou said, ''You must know, there are tens of thousands of black women in this country who reach their arms out to you.''

Ms. Angelou said that Dr. Shabazz was not only strong but kind, and a beloved friend. ''There is a major seam that has come undone in the quilt of my life,'' she said, fighting to control her sobs.

Then, turning to a subject that many speakers ignored, Ms. Angelou called on those present to nurture and protect Dr. Shabazz's grandson, Malcolm. ''God created him,'' Ms. Angelou said, to loud and sustained applause.

When Mr. Giuliani stepped to the pulpit, several dozen people in back pews began booing. But just as their chorus grew louder, former Mayor Dinkins, sitting in a front pew, stood, turned around and motioned with his hands for quiet. His gesture was greeted by applause, and the boos stopped.

Attallah Shabazz, with her five sisters standing in a huddle behind her on the pulpit, recalled the love her parents shared and said she wanted mourners to leave the church with an image of her dead father stretching out his ''amber arm'' to her dead mother, beckoning her to join him with the playful invitation: ''Come on, brown sugar.''

A Remembrance

Attallah Shabazz, in her address at the memorial service for Betty Shabazz, recalled her struggle for life after she was burned in a fire in her Yonkers apartment, and thanked the thousands who turned out to remember her.

''We kept asking ourselves, 'What gives her the strength to fight so hard?' We whispered in her ear, 'We're here, you're not by yourself, the prayers are big.'

''You don't have to fight so hard, Mama. We're doing it.'

''I want to thank you all for regarding the Shabazz family as that important, that significant. I'd like to ask you to look to the person to the left and to the right of you and genuinely say, 'I wish you the best.' By the power invested in us all, consider us brothers and sisters.''

Photos: Attallah Shabazz, the eldest daughter of Betty Shabazz and the slain civil rights leader Malcolm X, speaking at a memorial service for her mother. With her at Riverside Church are her five sisters, from left, Ilyasah, Gamilah, Qubilah (hands to face) and the twins, Malikah and Malaak. (Ozier Muhammad/The New York Times)(pg. B6)