Congregation, the vibrant Washington-based ensemble, opens its new album with "Urban Philosophy," the first session in what turns out to be an advanced class in vintage soul, funk and jazz.

With a tip of the hat to Stevie Wonder, Gil Scott-Heron and other masters of the idiom, the eight-piece band revels in the past without being constrained by it. Inspirational messages and sociopolitical issues shape the group's perspective, with fundamental faith and bitter realities sometimes clashing. Meanwhile, soul-gospel harmonies, sixteenth note guitar riffs and the tinkling sound of a Fender Rhodes keyboard conjure a time in pop music when funk, soul and jazz happily commingled, onstage and off.

Guitarist and songwriter David Boris deserves a lot of the credit for the album's emotional and atmospheric highs, as well as the sharp topical edge found on "Tell the Children" and other cuts. Throughout the album, his lyrics inspire vocalists Jenee Bevett and Aaron Hall to sing with passion and conviction, while his clipped chordal extensions and resonating wah-wah effects underscore the album's stylistic roots.

Not surprisingly, though, Congregation ultimately finds its greatest strength in numbers, as each member of the ensemble, especially saxophonist Frank Mitchell and percussionist Juan Giovani Travez, contribute to the band's sometimes fervent, sometimes slippery funk excursions.

Appearing Saturday at the Garage with Vibrosoul and Natural Distance. To hear a free Sound Bite from Congregation, call Post-Haste at 202/334-9000 and press 8127. (Prince William residents, call 690-4110.)