Until Thursday, fans didn't know the rest of the story behind Brantley Gilbert's "One Hell of an Amen."

Gilbert joined songwriters Brian Davis and Mike Dekle in celebrating the No. 1 success of the single at South in Nashville on Oct. 8. After the customary speeches and awards, Davis took the stage, tearing up as he thanked his wife and daughters for sticking with him as he chased his country dreams. The song was his first No. 1, but he frequently writes with Gilbert.

Dekle — a songwriting vet who scored hits with Kenny Rogers, Joe Nichols and more — also thanked the room before Gilbert took the microphone and told a story about his friend Josh Greene. Greene was an Army Ranger who returned home several years ago after watching a friend get killed when the Humvee he was in was bombed. Greene wasn't the same, Gilbert says, and for years he watched his longtime friend — a man who'd inspired several of Gilbert's songs — battle demons.

"I watched Josh struggles with substances, I watched him struggle with his mind ... you know when you know someone well enough to know something is on their heart?"

Adds Gilbert, "I never could figure out what it was."

Josh Greene's Army friend was Jonathan E. Lootens. Gilbert didn't know him, but invited his parents to attend a show in New York. The singer told his buddy they were coming, and he asked to come along. So finally, after years, Greene met the parents of his good friend.

“Josh finished the story,” Gilbert says, explaining how Lootens didn’t need to be on that mission. They argued, but eventually both left in separate Humvees. Then tragedy struck.

“Josh witnessed every second of what went down, but I saw a young man look into a mother’s eyes and tell her that he was not alone when he died. That he held his hand every second of the way.”

“One of the things she said was, ‘I just worried he was alone,’" Gilbert explains, "And Josh cried and said ‘He was not alone, I was right there with him. I never left him.”

“Josh is a new man,” Gilbert adds before looking at Lootens' mother and sister, who were in attendance. “That’s one more person that your man saved.”

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