Sandpapery. That’s a word we like to use when we talk about the rasp in someone’s voice, but few singers lived up to the metaphor’s paradox like Kenny Rogers. His voice was a rough, fine, reliable thing that made every sound around it feel smooth.

The grain of his timbre was genial and generous that way, and it gave his voice tremendous reach. By the mid-1980s, Rogers had become one of the biggest singers in any style, selling millions of albums, filling arenas and helping to make country music a planetary enterprise. But Rogers — who died Friday at 81 — didn’t do it on his own. “Some of the highlights of my life were the duets,” he told Rolling Stone in 2014. “I sing better on duets than I do by myself. It’s like running a 100-yard dash: You run as fast as you think you can, but you put someone alongside you who runs faster and you’re going to run faster.”

Rogers loved singing vocal harmonies, something he learned from his older sister in the church pews when they were kids. So it’s surprising to hear him describe the sympathetic ballads that defined his career — and his life — as competitive sprints.

We’ve Got Tonight,” the Bob Seger song that Rogers covered with Sheena Easton in 1983, has plenty of seize-the-night urgency, but he’s in no hurry. When the chorus surges, he supports Easton’s soaring high harmony, his boots planted firmly in the dirt. On “Make No Mistake, She’s Mine,” a simpatico duet with Ronnie Milsap from 1987, the pair make a nasty burst of psychological warfare in the divorcée dating pool feel as inviting as a warm bubble bath.

The Gambler,” Rogers’s signature megahit, isn’t a duet, but its lyrics re-create a dialogue between two strangers who meet on a “train bound to nowhere.” For a cigarette and a chug of whiskey, the gambler offers the big lesson that he’s learned at the poker table: When life feels as capricious as a game of chance, stay steely, but be decisive.

And even if we’ve sung that hook 10 million times at karaoke, it’ll always be strange to hear Rogers uphold the values of being stone-faced. That handsome little scrape in the back of his throat never signaled feelings being held back. Instead, his voice sounded experienced, lived in, a little worn, but emotionally forthright. The gambler probably should have been taking advice from Rogers instead of bumming cigs.

To best hear Rogers funnel life’s roughness into a spiritual smoothness, revisit “Islands in the Stream,” his 1983 duet with Dolly Parton and his grand achievement. The song was written by the Bee Gees, and its lyrics describe the profundity of human connection as a blindness, a deepness, an ambiguity, a clarity — all in a jumble of mixed metaphors that might only make sense when you’re falling in love.

Either way, the only metaphorical cues you really need are in the song’s title and the singers’ voices. Hers is clear, and sparkling, and pure. His is low, and sturdy, and patient. It’s an elemental love song about water and stone, and how their friction created the world we all share.