ST. PAUL, Minn. (AP) — "Only the children's voices soothe me," an anguished Sister Aloysius sings at the conclusion of "Doubt," the new opera based on John Patrick Shanley's Pulitzer Prize-winning play.

She has just confessed that she is tormented by uncertainty about the actions she has taken to drive out a priest whom she suspects of sexually abusing a child in the school where she is principal. And Shanley makes things just ambiguous enough that the audience, too, is left unsure of the truth.

But of this there is no doubt: The opera, with a libretto by Shanley and music by Douglas J. Cuomo, makes for a gripping 2 1/2 hours of theater. The work had its world premiere Saturday night in a production by Minnesota Opera, which commissioned it, and the enthusiastic audience at the Ordway Center responded with a standing ovation for the cast and creative team.

The loudest applause deservedly went to Christine Brewer, the distinguished American soprano who may have found the role of a lifetime as Sister Aloysius, an old-style disciplinarian whose devout faith does not inhibit her from resorting to devious tactics to defend her values.

On first hearing, it's hard to say how much of the project's success is due to the strength of Shanley's play and how much to Cuomo's musical setting.

The composer, who has written one previous opera called "Arjuna's Dilemma" and is perhaps best known for the theme music to TV's "Sex and the City," is clearly talented. He has an ear for subtle dissonance, and his inventive orchestrations are enhanced by judicious use of saxophone, piano and celeste. Shanley has rewritten a lot of the text to make it more singable and has opened up the play by adding choruses for children and for the churchgoers at St. Nicholas parish in the Bronx of 1964.

Like the play — and the movie adaptation that starred Meryl Streep — the operatic "Doubt" takes its time gathering steam. A series of light-hearted scenes in Act 1 seem to be mainly depicting a culture clash between the rigid Sister Aloysius and the more progressive Father Flynn. Cuomo's music for these early scenes is written in short, matter-of-fact phrases of sung dialogue, and he relies on rumblings in the orchestra to evoke the sense that something is not quite right.

But as Sister Aloysius becomes increasingly suspicious of the priest's relationship with the school's only black pupil, the music gains in lyric and dramatic power, culminating in their first confrontation at the end of Act 1. This arc continues throughout Act 2, where scene after scene reaches an emotional peak. The encounter in which Father Flynn wins over the young Sister James to his side takes on the feel of a seduction scene, their voices rising in overlapping harmony as they affirm that the "message of the Savior" is the "love of people." And Sister Aloysius's interview with Donald's mother — sung with rich, passionate tone by mezzo-soprano Denyce Graves — is riveting in its intensity.

It's in these later scenes that Cuomo gives Brewer a chance to exploit her plush upper register to its fullest. And her soaring vocal line as she moves toward victory and then gives voice to doubt imbue her character with a kind of tragic grandeur that words alone could not achieve.

The other soloists are first-rate as well. As Father Flynn, Matthew Worth complements his flexible baritone with a dashing, ingratiating presence that may or may not conceal a dark secret. Mezzo Adriana Zabala makes a sweet-voiced, earnest Sister James.

The production, directed by Kevin Newbury, is fast-paced and effective if perhaps overly elaborate. The many scenes melt seamlessly into one another thanks to Robert Brill's movable sets and Japhy Weideman's evocative lighting. Conductor Christopher Franklin leads the orchestra in a persuasive account of the score.

There are four more performances through Feb. 3.