Hundreds of mourners filled Westminster Cathedral on Saturday for the first public funeral of a London bombing victim, while the man's Christian mother and Muslim father bade farewell to their only son and launched a peace campaign in his name, so that "there might not be a tomorrow like a today or yesterday."

They came in African robes and flowing saris, business suits and blue jeans. People of different races and creeds, jet-lagged Nigerians and shell-shocked Britons, mourned Anthony Fatayi-Williams, 26, who died with 55 others, including the presumed bombers, in the July 7 terrorist attacks on London's transportation system.

Born in London, raised in Nigeria and educated in Paris, the junior oil executive was eulogized as a "citizen of the world" who cried easily, loved fiercely and dreamed largely. His mother crooned goodbye in the secret language they shared; his younger sisters wept as they scattered white rose petals on his grave. His coffin was borne by friends whose strong, young shoulders bent beneath a weight they did not expect.

"I am sure that the most prevalent thought in people's minds is: 'How would I react if this happened to me?' " said his cousin Tom Ikimi Jr., also 26. "I don't think there are any answers."

Like other family members and friends who spoke of their loss, then kissed their fingers and tenderly touched the casket's gleaming lid, Ikimi expressed admiration for the compassion and grace of the victim's mother, Marie.

Nearly two weeks ago, on the day she arrived from Lagos, Nigeria, to search for her missing son, Marie Fatayi-Williams went to Tavistock Square, where police had cordoned off the wreckage of the red double-decker bus where his remains would eventually be recovered.

Holding up his smiling picture before a sea of news cameras, the distraught mother instantly became the iconic figure of a tragedy Britain still struggles to comprehend.

"How much blood must be spilled?" she demanded. "How many tears shall we cry? How many mothers' hearts must be maimed? My heart is maimed."

Then she implored the public to "stop and think," adding, "We cannot live in fear because we are surrounded by hatred."

At the funeral Saturday, Tom Ikimi Sr., a former Nigerian foreign minister and the victim's uncle, recalled how the terrorist attacks of Sept. 11, 2001, had changed the United States. "Things cannot be the same again, whether for us, Anthony's family, or for London, or for the United Kingdom, or for the world," he said. "I bid Anthony farewell, and it will not be the same again."

Marie Fatayi-Williams, a Catholic, chose each prayer and hymn for the two-hour service in the capital's soaring Catholic cathedral.

As incense wafted past the marble columns and through the dim alcoves, the somber atmosphere abruptly shifted when Nigerian musicians struck up a rollicking African hymn, sung by a friend of the family who later described it as a gospel-tinged dirge. Heads snapped around in surprise, and two Englishwomen near the musicians gaped.

The mood reverted to hushed sorrow as the service wound to an end.

Anthony's father, Alan Fatayi-Williams, a retired doctor and a Muslim, announced the establishment of the Anthony Fatayi-Williams Foundation for Peace and Conflict Resolution.

"Yes, London, and it is Anthony today; New York, Madrid and thousands yesterday; who knows where and who tomorrow?" he began. "So that there might not be a tomorrow like a today or yesterday, we, Anthony's parents, have resolved to lend ourselves and our voice to finding peaceful ways to overcome violence and terror."

Outside the cathedral, a white hearse waited with a cortege of pearl Daimlers, and the parents faced news cameras once again. "Are you angry," they were asked. "Are you sad?"

"I am not angry," the mother said. "I am not sad." Her son, she would tell anyone who asked, was in a better place.

In keeping with Nigerian tradition, the family explained, the parents and elders did not go to the cemetery in Anthony Fatayi-Williams's north London neighborhood.

Instead, his friends boarded a double-decker bus and turned the hip-hop music up loud. Getting lost, they arrived late at the cemetery, conferring by cell phone.

Some wore T-shirts with their slain friend's image printed on it, over the words of Martin Luther King Jr.: "I refuse to accept the view that mankind is so tragically bound to the starless midnight of racism and war that the bright daybreak of peace and brotherhood can never become a reality."

At the grave site, the victim's sisters, Lauretta, 16, and Ayisha, 21, waited with baskets of rose petals, tugging purple African shawls over their shaking shoulders as they choked back tears for the big brother they called "Mr. T."

The backhoe waiting to bury him idled noisily on the road. They scattered their flowers and then released white doves. Then the backhoe moved in, and the earth covered a terrorist's victim.

Next to the grave, among the wreaths and bouquets, lay a large poster bearing the likeness of Anthony Fatayi-Williams. It was the same sign his mother had stood before that day in Tavistock Square.

In the picture, his face radiates joy. Above it are three words: "How Many More?"

The coffin of Anthony Fatayi-Williams, a victim of London's July 7 attacks, is carried at Westminster Cathedral as his mother, second from right, follows.