People hold up signs during a memorial for conservative activist Charlie Kirk on Sunday at State Farm Stadium in Glendale, Ariz. (AP Photo/John Locher)

GLENDALE, Ariz. (AP) — President Donald Trump and prominent members of his “Make America Great Again” movement paid tribute Sunday to Charlie Kirk, praising the slain political conservative activist as a singular force whose work they must now advance.

The memorial service for Kirk, whom Trump credits with playing a pivotal role in his 2024 election victory, drew tens of thousands of mourners, including Vice President JD Vance, other senior administration officials and young conservatives shaped by the 31-year-old firebrand.

“For Charlie, we will remember that it is better to stand on our feet defending the United States of America and defending the truth than it is to die on our knees,” Vance said. “My friends, for Charlie, we must remember that he is a hero to the United States of America. And he is a martyr for the Christian faith.”

Speakers highlighted Kirk’s profound faith and his strong belief that young conservatives need to get married, build families and pass on their values to keep building their movement. They also repeatedly told conservative activists, sometimes in confrontational tones, that the best way to honor Kirk was doubling down on his mission to move American politics further to the right.

“You thought you could kill Charlie Kirk? You have made him immortal,” said deputy chief of staff Stephen Miller. “You have no idea the dragon you have awakened, you have no idea how determined we will be to save this civilization, to save the West, to save this republic.”

Kirk’s assassination at a Sept. 10 appearance on a Utah college campus has become a singular moment for the modern-day conservative movement. It also has set off a fierce debate about violence, decency and free speech in an era of deep political division.

The shooting has stirred fear among some Americans that Trump is trying to harness outrage over the killing as justification to suppress the voices of his critics and political opponents.

Those close to Kirk prayed and the floors shook from the bass of Christian rock bands as the home of the NFL’s Arizona Cardinals took on the feel of a megachurch service.

“Charlie looked at politics as an on-ramp to Jesus,” said the Rev. Rob McCoy, Kirk’s pastor.

People began lining up before dawn to secure a spot inside State Farm Stadium west of Phoenix, where Kirk’s Turning Point organization is based. Security was tight, similar to the Super Bowl or other high-profile event. The speakers delivered their tributes from behind bullet-proof glass.

The 63,400-seat stadium quickly filled with people dressed in red, white and blue, as organizers suggested.

“I think that this is going to change things, and I think he made such a difference,” said Crystal Herman, who traveled from Branson, Missouri. “He deserves us to be here.”

Trump has blamed the “radical left” for Kirk’s death and threatened to go after liberal organizations and donors or others who he feels are maligning or celebrating Kirk’s death.

Dozens of people, from journalists to teachers to late show host Jimmy Kimmel, have faced suspensions or lost their jobs as prominent conservative activists and administration officials target comments about Kirk that they deem offensive or celebratory. The retaliation has in turn ignited a debate over the First Amendment as the Republican administration promises retribution against those who air what are seen as disparaging remarks in the wake of Kirk’s death.

A 22-year-old Utah man, Tyler Robinson, has been charged with killing Kirk and faces the death penalty if convicted of the most serious charges. Authorities have not revealed a clear motive in the shooting, but prosecutors say Robinson wrote in a text to his partner following the shooting that he “had enough” of Kirk’s hatred.

Turning Point, the group Kirk founded to mobilize young Christian conservatives, became a multimillion-dollar operation under his leadership with enormous reach.