Most 22-year-old men are just setting foot into the world, their graduation day a fresh memory and a reminder of the preparation for future paths. Their mindset is entry-level, and paying dues is necessary and imminent. They may be learning a trade and packing away experiences for the next step. They are eager, yet cautious.

Then there is guitarist/singer Davy Knowles, a 22-year-old with an almost untouchable guitar prowess, the emotional identity of a man three times his age and the voice to go with it, husky and rich and infected with the blues. Some would call him a prodigy. Some would wonder how such a phoenix with guitar in tow accumulated so many dues and so much life story in such a blink of time’s eye. Davy Knowles does not wait for the next step; he is the next step.

Those who gathered to see him play in a mid-sized Philadelphia club on this evening had one overriding thought in common: They were witnessing the second coming of the guitar. Davy and his band Back Door Slam played a mix of covers and selections from their two albums, the latest being the Peter Frampton-produced Coming Up for Air. Between sipping tea and grinning ear to ear, the Isle of Man native stung the crowd repeatedly with a brilliant take on Cream’s “Outside Woman Blues” followed by a mesmerizing ballad called “Gotta Leave.”

Mr. Knowles extends his reach as a blues prodigy by having a voice that is wonderfully mismatched with his age. It is a soul-searching, restless voice, full of just the right amount of vibrato and pain reminiscent of a man pining away for past days on a Mississippi back porch. The vox and the licks were wonderfully paired in crowd crushers like “As the Crow Flies” and an incendiary version of Rory Gallagher’s “Walk on Hot Coals.”

As he introduced a brand new song during the encore called “Be Gone in a Little While,” and explained that it hadn’t been recorded yet, a joyous fan interrupted with “We already love it!” The night ended with a raucous retooling of CCR’s “Commotion” and a unanimous feeling of “What the hell just happened?” City residents should not be surprised to see “Davy is God” tagged on any wall or door downtown, as was done for a certain Mr. Clapton in London so many years ago.