To anyone who’s dutifully trudged to watch their children in a holiday pageant, the prospect of going to see somebody else’s children in a holiday pageant — never mind paying for the privilege — is just about unthinkable.

But Les Freres Corbusier, the band of provocateurs that already hit pay dirt twice this year with “Heddatron” and “Hell House,” has issued this perverse challenge with a return engagement of “A Very Merry Unauthorized Children’s Scientology Pageant.” Last seen around these parts in 2003, Kyle Jarrow’s ingenious musical account of L. Ron Hubbard’s life and times — enacted by 10 cute-but-not-too-cute children — casts a chastising light on the seemingly harmless holiday tradition of gap-toothed devotion. Out of the mouths of these babes comes dogma.

Lisps, swooped notes, and all, the berobed 8- to 12-year-olds convey with endearing klutziness the birth of Scientology, a religion that found its roots in Hubbard’s sci-fi pulp fiction and that stresses the purging of all negative emotions. “You’ll operate with your analytical mind only,” Hubbard (William Wiggins) explains. “There won’t be any emotions to stand in the way of your success.” And if Dianetics can’t solve the problem, a fleet of sharp-eyed lawyers lies in wait. (Les Freres added the word “Unauthorized” to the title on advice from its legal counsel.)

Director Alex Timbers plays the inherent incongruity for all it’s worth. Even though the show has settled into a multiweek commercial run, the children still eye the audience anxiously, as if searching for the parents they know are out there somewhere. And Mr. Timbers gives the choicest material to the tiniest ones, as when 8-year-old Sean Moran imitates Tom Cruise’s facial tics or when little Dahlia Chacon fumbles her way through some of Hubbard’s more absurd bits of sci-fi theology.

For all its post-ironic delights, the presentation induces a fair amount of discomfort, both on a practical level (do these children understand why people are laughing at them?) and from the broader notion of “Jesus Camp”-style indoctrination. And while any religion can be made to sound a bit kooky if you emphasize the right factoids, the version of Scientology presented here is so ludicrous that one’s sympathy almost sides with the thetans and the engrams.

Les Freres Corbusier’s last outing — a largely sincere mounting of an evangelical “Hell House,” albeit one performed for an unusually skeptical audience — allowed the text to make its own damning case toward intolerance among Christians. (Not literally damning, but you know what I mean.) Messrs. Jarrow and Timbers stack the deck more this time: This Hubbard is a blatant snake-oil salesman, all but leering at the audience as he preaches the word and lines his pockets. As the entire company sings in the chilling finale, “Just don’t ask questions / And everything is clear.” Surely millions of people haven’t been converted by something this absurd, right? Right?

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Despite the involvement of the legendarily impious Christopher Durang, Christianity more or less gets a pass in “‘Twas the Night Before …,” the Flea Theater’s compilation of yuletide-themed riffs. Roger Rosenblatt toys with the notion of a Jewish Joseph working the manger crowd with a few Catskills-vintage jokes, and Elizabeth Swados offers a musical lament to the commercialization of the holiday, but the five playwrights included are more interested in finding a deeper meaning to the holiday psyche, one that transcends the trappings of holiday cheer.

Unfortunately, they haven’t found much. With the notable exception of Mr. Durang’s riotous “Not a Creature Was Stirring,” these skits range from pretentious (Mac Wellman’s “Before the Before and Before That”) to pandering (half of Ms. Swados’s “Holiday Movies” is devoted to a pair of elves, one of them white, engaging in Ebonics) to maudlin (Len Jenkin’s “Christmas Song”). The brief running times (about 10 minutes apiece) can be problematic, particularly for Mr. Wellman, whose cryptic, dense cadences require deeper immersion. Hearing a mere snippet of his work, as happens here, shows off its least welcoming qualities without allowing the viewer to recalibrate to his tempo.

Ms. Swados partially redeems the elf banter with a chorus of moviegoers who periodically offer a chipper choral tribute to Hollywood ultraviolence (“Everybody clap your bloody hands”), featuring inventive choreography by Mimi Quillin. Mr. Durang, meanwhile, uses the Clement Clark Moore poem that gives both his piece and “‘Twas” their titles as a pretext for familial rage and retribution. A family right out of Norman Rockwell sits for a Christmas reading of the poem — or as much of it as the father (Ben Beckley) can manage before either flying into a rage or unleashing club-wielding bats on his cowering family.

“Be quiet or I won’t read you the Christmas poem,” he screams,” and there will be no dinner, and no supper and bloody noses and no Christmas presents!” This level of sociopathic vitriol has been absent from Mr. Durang’s work in the recent past, and it’s nice to see it surge its way back. The holidays can do that to the best of us.

“A Very Merry Unauthorized Children’s Scientology Pageant” until January 7 (83 E. 4th St., between Second Avenue and the Bowery, 212-239-6200).

“‘Twas the Night Before …” until December 30 (41 White St., between Broadway and Church Street, 212-226-2407).