By Amir Vera, Eric Levenson and Sara Sidner, CNN

(CNN) -- Former Vice President Joe Biden drew from his Catholic faith to offer words of empathy to George Floyd's family and implored Americans to take on the fight of racial justice.

"Ladies and gentlemen, we've got to deal with the denial of the promise of this nation to so many people for so long," Biden said in a message delivered via video at Floyd's funeral. "It's about who we are, what we believe, and maybe most importantly, who we want to be."

Biden's comments came as family, friends and prominent figures gathered for Floyd's private funeral at The Fountain of Praise Church in Houston on Tuesday to celebrate his life and issue a clarion call for justice.

The service featured remarks by Biden, Rep. Al Green of Texas, Rep. Sheila Jackson Lee of Texas and Houston Mayor Sylvester Turner, and the Rev. Al Sharpton will deliver the eulogy.

Family members spoke about Floyd as a "gentle giant," and friends from high school and beyond fondly recalled his athletic prowess in football and basketball.

In addition, R&B artist Ne-Yo performed a rendition of "It's So Hard to Say Goodbye to Yesterday" by Boyz II Men and thanked Floyd.

"This man changed the world, he changed the world for the better," Ne-Yo said. "I just want to personally thank George Floyd for his sacrifice so that my kids could be alright later on."

The funeral comes two weeks after Floyd was killed while in Minneapolis police custody. His death sparked protests in the US and around the world, which have called for changes in policing and law enforcement's relationship with black and brown communities.

Family members of other black people killed by police, including Breonna Taylor, Michael Brown and Eric Garner, are also in attendance.

Boxing champion Floyd Mayweather is handling all the expenses for Floyd's funeral.

Biden: 'We must not turn away'

The service is a celebration of Floyd's life, said Mia K. Wright, the co-pastor of The Fountain of Praise church.

"In the tradition of the African-American church, this will be a home-going celebration," Wright said.

"Now you know what that means, that means foot-stomping, toe-tapping, shouting 'Hallelujah,' praising God, because we are celebrating his life," Dr. Remus Wright added.

In Biden's speech, he addressed Floyd's 6-year-old daughter, Gianna, and called on Americans to look through her eyes and question why racial injustice exists.

"Looking through your eyes, we should also be asking ourselves why the answer is so often too cruel and painful," he said. "Why, in this nation, do too many black Americans wake up knowing that they could lose their life in the course of just living their life? Why does justice not roll like a river or righteousness like a mighty stream? Why?

"Ladies and gentlemen, we can't turn away. We must not turn away. We cannot leave this moment thinking, we can once again turn away from racism," said Biden, the expected Democratic nominee for president.

Rep. Green called for "reconciliation for black people in the United States of America" in his remarks.

"This country has not reconciled its differences with us," Green said.

"We survived slavery, but we didn't reconcile. We survived segregation, but we didn't reconcile," he added.

Rep. Jackson Lee likened Floyd to the Biblical figures of Jesus and the prophet Isaiah.

"We know that centuries ago, they took a man, wicked men, put him on the cross. (They) did not understand that though they were intending wickedness, that out of much intention of wickedness came goodness," she said Tuesday.

"Your loved one, George Floyd, this secular world failed in its duty to intervene, failed in its duty to act, and failed in its duty to aid. But George Floyd answered the question in death when it was asked in Isaiah, 'Who should I send?' Oh God have mercy on us, there was a tall man by the name of Big Floyd who stood up and said 'send me.'"

After the service, Floyd's body will be escorted by the Houston Police Department into Pearland's Houston Memorial Gardens, according to the city of Pearland. His body will travel the last mile of the procession in a horse-drawn carriage, the city said. He will be buried next to his mother -- who Floyd called out for in his final moments.

The Rev. Mary White referenced that call as she offered a prayer of comfort during the service.

"We thank you for the life of George Floyd, oh God. That at a moment he called out for his mama, we believe that the ears of mamas across this nation reared up. That the ears of mamas across this world heard him cry even though for one mama, all mamas began to wail. We began to wail for our children. We began to wail for our grandchildren. We wail for men across this world because of one mama's call," she said.

Floyd's life in Houston

Floyd was born in North Carolina, where hundreds of people lined up Saturday for a public viewing of his casket. Floyd graduated from Jack Yates High School in Houston in 1992, where he helped the football team win the state title. He also played basketball as a power forward.

Before moving to Minneapolis, Floyd was well known in the Houston music scene, rapping with a group called Screwed Up Clik (SUC).

Actor Jamie Foxx are among those expected at the funeral, Lemon said.

Floyd died May 25 after former police officer Derek Chauvin pressed his knee into Floyd's neck for nearly nine minutes during an arrest.

Chauvin has been fired and charged with second-degree murder. Three other officers on the scene were charged with aiding and abetting second-degree murder and aiding and abetting second-degree manslaughter.

On Monday, thousands of mourners gathered at The Fountain of Praise church to pay their respects to Floyd. The memorial was the third stop in a series of events to celebrate his life.

Floyd was a huge role model for a lot of people, his brother, Philonise Floyd, said during Monday's visitation ceremony.

"He was the first person who everybody looked up to in our neighborhood because he was the first one to get a scholarship to go and play basketball or football when he wanted to do," Philonise Floyd said.

Floyd was someone who also had a beautiful soul, his younger brother, Rodney Floyd, said.

"If he was told he would have to sacrifice his life to bring the world together, and knowing him, I know he would've did it," Rodney Floyd said.

He added that he's still processing the death. "It seems unreal because, you know, every day is like waiting on that phone call. I'm still calling his phone number."

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