The Roots perform in Prudential Hall on Nov 16, 2019.

“You don’t define jazz. Jazz is just like…an attitude.”

The words of Miles Davis hung in the air this past weekend during one of the biggest events of this year’s TD James Moody Jazz Festival – literally and metaphorically.

DJ Logic had Davis’ musings about jazz playing in a loop over the speakers in Prudential Hall during the first act of an exceptional double bill: Veteran, genre-defining hip hop band The Roots, joined by A Christian McBride Situation, the funkiest of NJPAC’s Jazz Advisor’s musical collectives.

But the sentiment also served as a kind of a thesis statement, as the Arts Center’s signature festival expanded its definition of “jazz” to encompass funk, soul, rock, hip hop and even modern dance.

The festival’s first weekend also included appearances by blues legend Buddy Guy with gospel powerhouse Mavis Staples, soul queen Chaka Khan, After Midnight a tribute to the King Cole Trio with Clint Holmes, Catherine Russell and Billy Stritch, and even a modern dance performance by the Jersey City-based Nimbus Dance Company, which featured pieces set to the music of Nina Simone and Nancy Wilson.

But the festival came to a crescendo with Saturday night’s concert.

McBride attended the same Philadelphia high school as The Roots frontmen, Tariq “Black Thought” Trotter and Ahmir “Questlove” Thompson, so, as McBride said when he took the stage, “there’s a lot of history behind tonight.”

“Always nice to have a high school reunion on stage!” McBride said.

As the opening act, the Situation—including keyboardist and singer Patrice Rushen, vocalist Alyson Williams, Keith Loftis on saxophone, and dueling DJs  Jahi Sundance and DJ Logic—started things off quietly, although McBride played the bass guitar, instead of his usual upright bass. The group took jazz standards like “In a Sentimental Mood” and spun them out into elaborate, almost psychedelic jams. The band grew more energetic the longer they played, and in the end they wound up with a tribute to James Brown that had the audience swaying in the aisles.

And no one even thought about sitting down once The Roots arrived.

“I don’t want ya’ll to feel like ya’ll gotta sit still!” said Trotter, who paced the length of the stage relentlessly throughout the show as he rapped. “Let the music move you, do what you wanna do!’

The Roots are a big band, literally — the lineup for this concert included, in addition to Questlove and Black Thought,  two DJs, two keyboardists, a flautist, a trumpeter, a sax player, guitarist “Captain” Kirk Douglas and Tuba Gooding Jr. (aka Damon Bryson), who danced nimbly around the stage encaged in his gleaming sousaphone for most of the show.

The band — which has been the house band at The Tonight Show Starring Jimmy Fallon since 2014 —  reached through decades of their catalog for the setlist.

“This is a grown-people party, so we’re gonna revisit some of the classics,” Black Thought announced early in the concert, diving into the early-90s jam “Looking at the Front Door” by Main Source. A few minutes later, the Roots’ “Act Too” evolved into the ‘90s favorite, Wu-Tang Clan’s “Shimmy Shimmy Ya.” Later, as the band’s brass section took a quick break (sousaphones are heavy), Black Thought, Questlove and Kirk Douglas alone took on the band’s GRAMMY Award-winning ballad “You Got Me” (with a tiny alteration in the lyrics, so that the “politickin’ sister…from New York City” was relocated to “Brick City.”).

As Douglas stepped into the spotlight, the song evolved into a jam that incorporated Sade’s “The Sweetest Taboo,” Lil Nax X’s inescapable summer hit “Old Town Road” and even Rodgers and Hammerstein’s “My Favorite Things.”

The range of the music, the virtuosic soloing by all the players and the wildly improvisational nature of the show easily made the case that that The Roots are a jazz band when they want to be — even as the nonstop beats held up their reputation as a group that throws a phenomenal party of a live show.

More jazz of all kinds is slated for the TD James Moody Jazz Festival at NJPAC this  weekend, with guitarist Lee Ritenour and pianist Dave Grusin performing Thursday, pianist Christian Sands playing a tribute to the late, great Erroll Garner on Friday, tap legend Gregory Hines Tappin’ Through Life with the DIVA Jazz Orchestra Saturday, and singers from around the world scatting to beat the band at NJPAC’s Sarah Vaughan International Jazz Vocal Competition on Sunday.