Those who consider fundamentalist religion and the fervor of the born-again Christian to be off-limits as topics for humor are certain to find "Tent Meeting" outrageous, irreverent and nervy as all get-out. It seems safe to assume, for example, that this will never be the senior class play at Liberty Baptist College.

If, on the other hand, the zeal of the Bible thumpers and their certainty that God has sent them to the head of the class strike you as fruitful areas for satire, you will welcome "Tent Meeting" as one of the most original comedies in seasons. Not since Arena Stage lowered the boom on Tartuffe has disorganized religion taken it quite so robustly on the chin. Jesus doesn't come off too well, either -- or at least the armless, legless, largely organless baby in the picnic hamper who may be the reincarnation of Jesus for our times. But who ever said theater has to be fair?

The runaway hit of last spring's new play festival at the Actors Theatre of Louisville, "Tent Meeting" opened a six-week run Wednesday night in the Kennedy Center's Terrace Theater. Gleefully perverse, it is also savagely funny as it traces the saga of the Tarbox family, unto whom is born 1) the Lord Jesus Himself, 2) a girl named Arlene-Marie or 3) a turnip. It depends, you see, on who's doing the talking.

The Rev. Ed Tarbox (Levi Lee), the white-haired patriarch of this redneck clan, is convinced it's God's child and plans to erect a new city of faith on its tiny shoulders (although it's not certain the child has shoulders). Becky Ann (Rebecca Alworth Wackler), the reverend's simple-minded daughter and the unwitting holy mother, admits that God sired her infant; she's even immortalized the moment of conception in a chipper ditty, "Raped by God," which she sings to ukulele accompaniment. But she also insists on naming the child Arlene-Marie and persists in referring to it as "she."

Darrell (Larry Larson), the oafish son, can only see a vegetable in the hamper and assumes it's the just fruit of an incestuous relationship between his father and sister. With anger, born in part of jealousy, he eyes the swaddled creature and sputters, "We'd have to hang a pork chop around your neck to get the dog to play with you." Then after a reflective pause, he adds, "If we had a dog and you had a neck, which we don't and you don't."

But it's Reverend Ed who calls the shots -- actually, he thunders them forth as if a pulpit were permanently attached to his person. So the family -- chosen or not -- is speeding north in a trailer from Arkansas to Moose Jaw, Saskatchewan. There, the infant is to be baptized Jesus O. Tarbox in a tent meeting that will herald the dawn of a new age. The trip is fraught with supernatural incidents, moral betrayals and spiritual setbacks, not to mention a hearty game of "Go Fish" -- all of which Reverend Ed sees as the equivalent of the flight into Egypt and confirmation of God's plan. God, in fact, has been sending directives to the Tarboxes in the form of typewritten letters, mysteriously delivered. The trouble is, the messages have become increasingly cryptic and the grammar is simply awful.

The authors of this fable just happen to be the three cast members, which helps account for the truthfulness of the performances. Not only have they concocted a dark and savory satire, but they have also tailored themselves some richly theatrical roles, and the fit, in each case, is well nigh perfect. Lee's preacher is an impressively pot-bellied pillar of sanctity, mighty in his rage, petty at cards and utterly shameless when it comes to inventing scripture to suit his purposes. To back up his silver-voiced rhetoric, he's got a quick and deadly hammerlock. Like the dictatorial characters of classical comedy, his obsession renders him as funny as the strength of his fanaticism makes him scary.

Larson plays the sniveling Darrell with a shaky bravado that is forever dissolving into apology, grovel and retreat. In his own moon-faced, squeaky-voiced way, the son is as fraudulent as his father -- he proudly passes off his hernia scar as a bayonet wound acquired in the war in "France, Europe" -- but he doesn't have the courage of his delusions. When the chips are down, so, unfortunately, is Darrell. His attempt to foment rebellion in the trailer fails miserably, leaving him no option but to submit to religious conversion and embrace his father's crackpot cause. Larson plays the transformation with hysterical, tongue-talking brilliance, ending up as beatific as a lobotomy.

But it is Wackler's performance as Becky Ann that gives "Tent Meeting" its enigmatic fascination. On the surface, Becky Ann is dimwitted, docile and plain as her full-length apron. She's taken to stuffing wads of cotton in her ears -- it allows her "to keep the music in," she explains -- and most of the time, she seems blissfully unaware of what's going on around her. Doesn't even want to know.

Little by little, however, Wackler indicates that this sorry creature may be more than she appears. It has to do with the sweetness of her smile when she's bending over the picnic hamper; the cheerful willingness with which she accepts one preposterous turn of events after another; the glints of irony in her sad eyes that give the lie to her otherwise dumbstruck, slack-jawed mien. At first, you think Becky Ann is the village idiot. By the end, you wonder if she isn't actually following a grand, secret destiny.

That may be the ultimate paradox of this tantalizing play. Even as it is excoriating the excesses of fundamentalist behavior, it refuses to discount the possibility that God's incarnation really is lurking in that picnic hamper. "Tent Meeting" revels in the outlandish. But the thought may occur to you that outlandish, in this instance, could just be another word for miraculous.