A few years ago, the folks at PEN New England created the Song Lyrics of Literary Excellence Award to celebrate the craft of songwriting. It was an inspired idea.

The inaugural recipients, chosen by a committee whose members know a few things about phrasing, were Chuck Berry and Leonard Cohen, followed by Kris Kristofferson and Randy Newman.

At the JFK Library on Monday, Elvis Costello, who serves on the selection committee that also includes Bono, Rosanne Cash, Peter Wolf, novelist Salman Rushdie, writer Bill Flanagan, and poets Paul Muldoon and Natasha Trethewey, was on hand to introduce this year’s honorees: John Prine and Tom Waits and his wife, Kathleen Brennan.

The beauty of the Song Lyrics Award is that it has nothing at all to do with an artist’s commercial success, but instead with the way they use language to achieve, in song, something very much like literature.

Prine, who emerged from the Chicago folk scene in the early 1970s, has written such sweet, understated gems as “Angel From Montgomery” and “Lake Marie.” Bob Dylan once described Prine’s songbook as “Midwestern mind trips to the nth degree.”

Monday, the 69-year-old Prine, who’s endured two bouts of cancer in recent years, was feted by a few of his famous admirers, including longtime friend John Mellencamp, who stepped to the microphone and spoke/sang a verse from Prine’s “Sabu Visits the Twin Cities Alone.”

“Now, who writes songs like that? Sophisticated and simple,” said Mellencamp, dressed in jeans, white T-shirt, and a black vest and jacket. “Two people come to mind, God and John Prine.”

Mellencamp became emotional as he admitted he’d lost touch with Prine when he got sick—“John, I’m sorry for not calling you all those years”—but Mellencamp said he relished the opportunity now to celebrate a songwriter he called “a natural-born earth shaker.”

Cash, accompanied by Costello on acoustic guitar, performed one of Prine’s best known and oft-covered songs, “Hello in There,” which brought many in the hushed audience—and Cash herself— to tears. Country star Sturgill Simpson then thanked Prine for his “humanness and realness.”

“You can’t put a price tag on what you’ve given to the world,” Simpson said in a halting voice. “For that I’ll always be grateful. You’ve done more for me than you’ll ever know. I love you, brother.”

Prine seemed tickled by the honor, and reckoned that some of his teachers at Proviso East High School in Maywood, Ill., were probably “twirling in their graves.” He then picked up a guitar and played “Souvenirs,” with its chorus: “Memories, they can’t be boughten/They can’t be won at carnivals for free/Well it took me years to get those souvenirs/And I don’t know how they slipped away from me.”

Waits, whose varied discography dates to the ’70s, has been writing songs with his wife for more than 30 years. He acknowledged that it’s not always easy—“sometime the fur flies, the feathers fly”—and their sensibilities can differ.

“She had a lot of questions when we first started writing together,” Waits said in his customary Cookie Monster growl. “Like, ‘Why does that guy have to be missing an eye?’”

Irish author Colum McCann paid tribute to the couple’s partnership and what they’ve created. “They illuminate the landscape and then they plunge it dark again,” McCann said. “The world as we have it is their lucky anthem. They fling it open with their lives and a few strings and a voice that was somehow scratched by heaven.”

Costello, who was an angry young man when he met Waits for the time at the Tropicana Motel in 1978, sat at the piano and played a mesmerizing version of the Waits/Brennan composition “Take It With Me.”

After a few kind words from filmmaker Jim Jarmusch—the director cast Waits in “Down by Law” and “Coffee and Cigarettes”—Waits reluctantly addressed the crowd.

“When I first heard about this, I said, ‘Give them the P.O. Box,’” he said, perhaps only half joking. “That’s what I usually do. But they said, ‘You gotta come down and get it.”

Talking about working with his wife, Waits paused.

“We’re different,” he said. “If two people know all the same things, one of you is unnecessary.”