Though it wasn’t released until more than two months after his death, Judas Priest frontman Rob Halford says his longtime friend Ozzy Osbourne was able to hear and was, in fact, pleased with Priest’s new version of Black Sabbath‘s “War Pigs” that features Osbourne’s vocals.

“The absolute thrill for us all is he, with Sharon, listened to the final, finished mixing and he was grinning – he was smiling and he was very happy,” Halford exclusively tells Billboard. “This all came back to us in a note from Sharon, saying he was absolutely thrilled and delighted that we go to do something together musically in this particular way. So for him to do that and then two weeks later to go where he went was just unbelievable.”

Osbourne passed away on July 22 at the age of 75, just 17 days after his final performance — with his own band and Black Sabbath — at Aston Villa Park in his hometown of Birmingham, England. Judas Priest was also formed there in 1969, a year after Sabbath.

“War Pigs (Charity Version)” was released online Sept. 26, with proceeds going to Priest guitarist Glenn Tipton’s Parkinson’s Foundation and the Cure Parkinson’s nonprofit that the Osbournes support. A CD version of the single is due out later this month.

“It was very beautiful but very poignant for us to unite for the first time ever in the history of both (acts) on a song that’s beloved by millions of metalheads around the world,” Halford says. “To put these two bands — Priest and Sabbath — together in this format is just sensational.”

The new “War Pigs,” with a pre-existing recording of Osbourne singing the track from Black Sabbath’s 1970 album, Paranoid, was an outgrowth of some challenging logistics that surrounded the Back to the Beginning show.

As longtime friends and an Ozzfest veteran, Priest was, of course, asked to be part of the bill. But the band had already committed to play as part of Scorpions’ 60th anniversary show in Hannover, Germany, on the same night. And while there was some consideration to flying Priest between the two events the logistics didn’t work out.

“We were absolutely gutted that we couldn’t take part” in Back to the Beginning, Halford says. “But then we immediately thought, ‘Is there anything we can offer? Is there anything we can put to Ozzy, to Sabbath, to the event just to show the love that we have for him and the band and everybody?”

Recording “War Pigs” was a “no-brainier,” according to Halford. Judas Priest has long used the song as pre-show music before the band hits stage. “It’s just a great, huge rallying cry to get all of the metalheads ready and focused that, ‘OK, Priest’s gonna hit the stage,’” Halford says.

The group hit the studio with Andy Sneap, who’s produced Priest’s last two studio albums and tours in Tipton’s stead.

“We gave it what we call the Judas Priest-style heavy metal treatment,” Halford says. “It’s such a brilliant, classic track that you can’t really mess with it. You’ve got to stay true to the core components of the song, and that’s what we did. We added a little bit of the Priest dimension because we wanted to put something of our signature flavor into the track,” which was achieved primarily via drummer Scott Travis’ distinctive fills with some guitar nuances by Tipton and Richie Faulkner.

“Everybody did a magnificent job,” Halford notes, and Sharon Osbourne came back with one suggestion. “She said, ‘Hey, is there a possibility we can get Ozzy singing with Rob on the track?’ I was doing the happy dance, ’cause here for the first time in my life I have the opportunity to sing with Ozzy, so that’s what we did.”

And Halford was pleased by how well his vocals meshed with Osbourne’s when they were added.

“The way I sing on this particular song is in the same kind of realm as Ozzy,” he explains. “I would never say I’m trying to copy Ozzy; it’s just the way… maybe something in the water in Birmingham — or in the beer in Birmingham, ’cause we were both drinkers. But we have voices that are very, very close to match up. It’s kind of spooky — when Ozzy sings, when I sing, the way the two voices are put together it’s absolutely magical. We’re all just so happy that we were able to do justice to such a great moment in metal.”

Nevertheless, Halford says it took some time for him to be able to listen to “War Pigs (Charity Version)” after Osbourne’s death.

“I would get through 30 seconds and I would just have to switch it off because I was just so overcome with emotion,” he says. “To be in the same experience of that moment with Ozzy was just too much for me, and it was too close. I’m still grieving. It’s still very tough for me because of my friendship and my love for the man. It took me awhile to listen to the whole song in one go without any breaks, and now I can.”

Priest still plays Sabbath’s “War Pigs” before the band hits stage, and since Osbourne’s death the group has paid tribute to him — and other deceased musicians — during the song “Giants in the Sky.”

The charity component, meanwhile, came from the Priest camp and was readily agreed to by Sharon Osbourne. “It’s a great back end, as far as the good it’s going to do and… be added to that great haul of cash that was drawn up on the (Back to the Beginning) show,” Halford says.

Judas Priest is currently on tour with Alice Cooper and Corrosion of Conformity, wrapping up Oct. 25 in Houston. The group’s lone announced date for 2026 so far is the Bloodstock Open Air festival in the U.K.

Halford says he’s also hoping Priest will make a 20th studio album in the near future to follow up last year’s Invincible Shield, which debuted at No. 1 on Billboard‘s Top Hard Rock Albums chart and No. 4 on the Top Rock Albums survey.