For those of us whose hearts are breaking over the fate of New Orleans and its roots-music culture, seeing and hearing a performance by Dr. John is like attending a secular church service held at an o

For those of us whose hearts are breaking over the fate of New Orleans and its roots-music culture, seeing and hearing a performance by Dr. John is like attending a secular church service held at an oversized piano bar or a glorified juke joint: It's practically a required ritual, the least we can do to give props.

Florida-based fans and a few evacuees alike found a measure of solace and a joyful celebration of all things New Orleans when the singer, pianist and composer born Mac Rebennack took the stage. The show was held at the historic Tampa Theatre, a 1920s-era movie house and concert palace decorated with ornate carvings and topped with a ceiling resembling a starry night sky.

Dr. John, dressed in a royal blue suit, black fedora and white loafers, a silver earring in his right ear, used a walking stick to make his way to a black grand piano decorated with a purple sash and topped with a skull that faced the audience. He held forth alone, without the benefit of his Lower 911 band: The result was a palpable intimacy, as if the Crescent City's first physician of funk were hand delivering good-time medicine to the spiritually ill.

The show, on the whole, felt like an artfully freeform grab bag of tunes from his vast repertoire. He included several pieces from last year's "N'Awlinz: Dis Dat or D'udda" CD, and opened with a hard-pounding version of Jerry Lee Lewis's "Whole Lotta Shakin' Going On."

As per his usual strategy, Dr. John tricked out the opening sections of several standards, including "Blue Skies," capped with a string of fluttering notes; a rollicking "Goodnight, Irene"; and a tangy reading of "Makin' Whoopee," which he recorded 15 years ago as a duet with Rickie Lee Jones for his "In a Sentimental Mood" album (it subsequently landed on the big-selling "Sleepless in Seattle" soundtrack).

Plenty of tunes, of course, were distinctly representative of the New Orleans sound: He turned in a swaggering version of "Tipitina," the rumba-boogie classic by Professor Longhair, a major influence on Big Easy musicians; and he sang and talked his way through "Marie Laveau," a spooky tale about the 19th century voodoo queen, spiced with references to hoodoo, snake dust, black candles and the St. Louis Cemetery.

John's "Right Place, Wrong Time," the 1972 chart hit produced and arranged by Allen Toussaint, was a requisite part of the program, but it wasn't uninspired, and it provoked interactive audience response on the song's "ooh" sections. A newfangled "When the Saints Go Marching In" was all melancholy beauty.

Naughty songs, laced with sexual double entendres, were part of the mix, too, with the suggestive "Hen Layin' Rooster" and other tunes. And revenge and murder ("operatin' ... mutilatin' ... strangulatin' ... crematin') were the subject of dark comic ditty "How Come My Dog Don't Bark (When You Come Around)?"

The hard-charging blues boogie of "Sweet Home New Orleans," revised to reflect Hurricane Katrina's destruction and the disastrous aftermath, was an emotional highlight of the 100-minute concert: "We sho' comin' back, twice as strong," Dr. John sang, prompting a standing ovation.