“We’ve never let that one out in public before,” he confessed. “That was fun!”

Fun seemed to be what just what the Stones were determined to have as they delivered a scorching 22-song set at Boston’s FleetCenter Tuesday night. They mixed the old with the new, the familiar with the more obscure, and through it all proved that even after 40 years, there is still plenty of tread left on the tires.

From the moment they burst on to the stage at 8:55 p.m. until the moment they left more than two hours later, the Stones sustained an energy level that belied their age.

Their first number, “Street Fightin’ Man,” was a statement that the Stones had only begun to fight. They followed with “If You Can’t Rock Me,” and when Jagger jabbed a finger in the air during the refrain: “If you can’t rock me, somebody will!” he seemed to be issuing a challenge to the sellout crowd.

None was needed. The audience, much of it graying and balding, remained on its feet from start to finish in rapt appreciation of its ageless rock and roll heroes.

Jagger, knighted by Queen Elizabeth II in June, played the court jester as he strutted and swaggered and gyrated his hips, acting more the 19-year-old he was when the Stones first started than the 59-year-old he is today.

He played acoustic guitar on “Don’t Stop,” one of four new songs included on Forty Licks, a 2-CD greatest hits compilation due out in October. Later, after a show-stopping rendition of “Tumblin’ Dice,” Jagger yielded the microphone to Keith Richards and left the stage while the venerable Richards crooned his way through the sardonic “Slipping Away,” and the effervescent “Happy.”

The latter song was appropriate because Richards, who has not always seen eye-to-eye with Jagger, seemed especially happy to be back on stage. “We’re having a great time up here,” he commented, and there was no reason to doubt him.

Jagger returned for the “Love Train” send-up, and a couple of songs later, the Stones tried another piece they had never before done live, the jazzy “Can’t You Hear Me Knockin'” off their Sticky Fingers album. It started flat, one of the few times that happened all night, but guitarist Ron Wood saved it anyway with a stellar solo.

No Stones concert would be complete, of course, without a touch of the lewd. During “Honky Tonk Woman,” a cartoon appeared on the giant onstage video screen co-starring a virtually-naked woman and the Stones lips-and-tongue logo. The animation left little to the imagination.

The band wrapped up the show with several of its signature songs, including “Satisfaction,” “Brown Sugar,” and encore numbers “Sympathy for the Devil,” and “Jumpin’ Jack Flash.”

The Stones have two more Boston-area stops, first at 68-thousand-seat Gillette Stadium in Foxboro, followed by a show at the 2,800-seat Orpheum Theater. The pattern of playing large, medium and small venues will continue when the 25-city, 40-show tour moves on to Chicago, Philadelphia and New York.