When Carter Stanley died of drinking in 1966 and the best bluegrass duo in the world ended, it must have been hard for Ralph Stanley to keep going. It must have seemed like the end of the world. You made a living and a life standing next to your brother on a stage, you did it for 20 years, you made a name as two people. But in bluegrass, the songs are bigger than you. The songs are a manner of being, and the songs are God.

So Ralph Stanley had a mission to keep going, and he did, for 50 more years, long enough to see himself become the single most important living performer in his idiom. He's dead now, at age 89. But he never sounded that old. He sounded at least twice that old.

The key to enjoying bluegrass music, if you don't listen to it recreationally — and, hell, maybe if you do listen to it recreationally — is to love how old it all sounds, how much it feels like history. If you listen to a latter-day Ralph Stanley song, you don't think Oh, there's an 80-year-old man singing in a world that has iPhones in it – you think Oh, there's an 80-year-old man singing in a world that doesn't even have cars in it.

That's a tool of enormous power in bluegrass, which leans heavily on traditionals, songs handed down like old recipes, and even more heavily on gospel numbers that emphasize themes bigger than time. As the Alfred Brumley composition "This World Is Not My Home" goes, "This world is not my home, I'm just passing through." We get here, we set our bags down, and in the blink of an eye we're off to eternity.

Ralph Stanley was a damn fine banjo player, but it was his voice that mattered most. His voice underlined the message, a message that constantly recurs in his gospel performances. Those songs are emotionally potent in the way gospel needs to be emotionally potent. They take the deepest, oldest sorrows and release them through catharsis and community as joy, rendered up to God.

His most powerful performances are all gospel, because that's where his heart was, and you can hear it. "Rank Stranger," "The Fields Have Turned Brown," "I Am Weary (Let Me Rest)," "Lift Him Up, That's All," "Beautiful Star of Bethlehem," "Where the Soul of Man Never Dies." His tool was a voice like mountain wind, and for his whole life he used it to share his faith.

I emphasize this because religion was the most important component of Ralph Stanley's career, and the message of a performer is always the first detail to go when a performer dies. In death, about half of Johnny Cash's legacy became a Nine Inch Nails cover and a picture of him flipping the bird, and he got claimed by any sect of real music, man aficionados who wanted him that second, but to the end he'd tell you God was his main career concern. It would likewise be easy to reduce Ralph Stanley to his ethereal and bone-chilling rendition of "O Death" that anchored the Coens' O Brother, Where Art Thou? and the subsequent bluegrass revival. This revival, while well intentioned, occasionally leaned too heavily on a post–Bob Dylan conception of the old, weird America; too heavily on Harry Smith's Anthology of American Folk Music. The undertone was that bluegrass and gospel music, like that of Ralph Stanley, was a kind of American kitsch, a bit of a fashion statement, an edgier and less accessible variant of collecting, say, old postcards. But it's not that. It must never be that. Songs need cultural context, and we cannot condescend to our country's music by ignoring its stated purpose.

If you take Ralph Stanley for who he was, where he was from, and what he was singing about, you'll find a man who spent an impossibly long recording career preserving a way of life and a kind of music that's easy to render up to cultural anthropology and neglect. But if you don't neglect that, you'll hear an impossibly beautiful and lonesome voice, a voice like a ghost in a forest you heard once and kept looking for but never found again.

I wandered again to my home in the mountains

Where in youth's early dawn I was happy and free

I looked for my friends but I never could find them

I found they were all rank strangers to me

Everybody I met seemed to be a rank stranger

No mother nor dad, not a friend could I see

They knew not my name and I knew not their faces

I found they were all rank strangers to me.

They've all moved away, said the voice of a stranger

To a beautiful home by the bright crystal sea

Some beautiful day I'll meet them in Heaven

Where no one will be a rank stranger to me.