Billy Ray Cyrus performed a heartrending version of Amazing Grace at the funeral for slain Sgt. Ron Helus Thursday in Westlake Village.

Seated in a chair at the front of Calvary Chapel Community Church, the country music star strummed on a guitar and sang the Christian hymn with passion as a choir backed him.

 After the song ended, Cyrus said he was honored to take part in the service.

"It's humbling to be in this room with so many heroes," he said. 

"Today we're here to honor this hero, Mr. Ron Helus, that's touched us all here in America and touched the world," he continued. "I met the family earlier and I told them that they're probably going to need to change the definition in the dictionary of hero. I think from now on, it can just be a picture of Ron Helus and his bravery."

"This man is a true definition of a hero," Cyrus added, before performing his single Some Gave All.

Helus was one of 12 people killed last week after a gunman opened fire inside the Borderline Bar and Grill in Thousand Oaks.

As others ran to safety, the 29-year veteran of the Ventura County Sheriff's Office rushed inside to confront the gunman and paid the ultimate price.