A COMMON THEME in science fiction--besides space creatures, stellar explosions and single combat with the Emperor of the Universe--is the paradoxical box that is bigger inside than out. Though it seems unlikely, Stephen DeAngelis's production of Stephen Schwartz's Godspell takes place in just such a box. The Charles Playhouse, home of Godspell, is tucked behind the larger, more brightly lit Schubert Theater. The stage is small and the theater itself seats only 500.

But somehow the interior of the Charles Playhouse expands. It has to, to accomodate the exuberance of Godspell actors and actresses. As they march out into the aisles to sing and clap their way through "Prepare Ye the Way of the Lord," the entire house shakes--except for buoying waves of enthusiasm, the roof might have collapsed long ago.

In fact, the theater's small size is an advantage. The cast interacts directly with the audience, shaking hands, telling jokes and encouraging audience participation in an onstage game of charades. As John the Baptist enters, he actually sprinkles water into the seats. The audience surrounds the stage on three sides, which brings the actors out into the house and adds to the intimate feelings.

First produced in Boston in 1971, Godspell retells the Gospel according to St. Matthew in a modern frame. DeAngelis has taken the updating process one step further. References to E.T., Valley girls. Olivia Newton John and Steve Martin bring the biblical parables into the '80's. It is apparent that the actors find this as amusing as the audience.

Several of the performers also seem larger inside than out B.J. Jefferson's "Bless the Lord" and her numerous minor numbers prove that a theater filling voice can come from inside one woman Jefferson moves easily from upbeat rock to five and soul in "Bless the Lord," and "B.J." call the actors use their own names for their characters dominates many of the parables Debra Hauptman is also solid as a sensual, slightly raunchy but still endearing Debra.

IT IS DISAPPOINTING that, despite the coziness, many actors need a microphone to be heard One of the few who do not need help is Sam Scalamoni. When he first appears in the back of the dark theater singing "Prepare Ye the Way of the Lord" and sporting a multi-colored tailcoat, Scalamont fills the house by himself. Scalamont, cast as both John the Bapost and Judas, nandies madness subtly the switch from Christ's right-hand man to His betrayer, gradually separating himself from the other joyful, rag-clad actors. He easily outshines James Weatherstone, who is uninspiring as Jesus, and in their vaudvillian duet. "All for the Best," Scalamoni dominates the stage. Surprisingly, since his is the outstanding performance in the show, Scalamont is only an alternate for Rich Hebert, who usually plays the role.

Technically too. Godspell takes simple measures and creates the spectacular. The scenery is sparse, a chain-linked fence is the only backdrop and some cloth scraps, planks and two sawhorses become the roadway for the Good Samaritan and the pigsty for the prodigal son, thrones for sinning kings and wise judges, and the table for the Last Supper. The lighting for the dance numbers includes a strobe light in "Bless the Lord" and red and green spotlights in several other numbers. In the "Finale," easily the most moving number a single beam shines down on Weatherstone, while the other characters, dancing wildly are silhouetted against a red light.

Not all the actors are as skillful as Jefferson and Scalamoni, Jessica Lichtner's "By My Side" lacks the vitality of the dances without substituting lyric beauty, and Weatherstone's unspectacular performance in what should have been the dominant role deters from the overall effect.

Gags, puns and impersonations of celebrities from Vivien Leigh to Rodney Dangerfield abound throughout the show, occasionally detracting from the seriousness of the parables when they get out of hand. As Jesus tells his disciples that if a man takes their shirts, they should give him their coats, one character chimes in with. "Give 'em your tired, give 'em your poor," while another is shushed by his friend when he adds, "Give 'em hell." One particularly moving exchange is Christ's response to a character's complaint that she is an only child, "So am I," he says.

But the overall joyousness of the production more than compensates for its flaws. Godspell combines a classic score (the original cast album sold over a million copies) with fresh energy and vitality. Originally scheduled to close on February 20. Godspell has extended its run for two additional weeks. The extra performances are a reprieve to be taken advantage of. Catherine I. Schmidt