In recent years, English National Opera has abandoned its long-standing opposition to surtitles, belatedly (in my view) recognising that singing in English doesn't do a lot for accessibility if only the front half of the stalls can hear it clearly. But if last night we found them going to the opposite extreme, singing in Sanskrit and providing no translation apart from the occasional quotation projected onto the back wall, it can only be because they were performing Philip Glass' Satyagraha, with its libretto by Glass himself and Constance DeJong after the Hindu scared text the Bhagavad Gita.

Satyagraha is the second of Glass' three portrait operas, sandwiched between Einstein on the Beach and Akhnaten, and if in Einstein he and co-creator Robert Wilson felt that the subject being so well-known allowed them go beyond simply telling the story of his life, Satyagraha is also far from a straightforward narrative. For one thing, although the three acts are entitled Tolstoy, Tagore and King, representing (from Gandhi's point of view) the past, present and future of his idea of "satyagraha" (literally "truth force", though often translated as nonviolent resistance), the timeline is far from chronological.

For example, we first meet Gandhi much as we do in Richard Attenborough's film, having been thrown off a train because he refused to vacate the first class carriage his ticket entitled him to. But the setting for this scene is actually "The Kuru Field of Justice", site of a mythical battle between two royal families in which Krishna enjoins Arjuna not to be faint-hearted now the moment has come. The next scene sees us at Tolstoy Farm in 1910, where South African Indians of all castes worked together and alongside Satyagrahis of other races, sharing the physical labour, after which we jump back to 1906 and the moment when all Satyagrahis took a personal vow to resist the "Black Act" that required Indians to carry permits.

To say that ENO (in partnership with the Metropolitan Opera in New York and renowned theatre company Improbable) shy away from a literal production of this piece begs the question of what that could possibly be, when what's sung is not so much an expression of this or that character's thoughts as an abstract philosophical commentary on the situation. Director Phelim McDermott is an accomplished musician himself (not something one can take for granted with opera directors), and he and set designer Julian Crouch have come up with a wonderfully evocative staging, remarkably beautiful even if you have to sometimes just go with it without thinking too hard about what it means. Highlights for me would be the burning of the passbooks in Act II Scene III, and the Where the Wild Things Are-like first scene of that act. The inspirations for the three acts appear one by one as a medieval triptych on the back wall, culminating with Martin Luther King seen from behind giving (presumably) his speech at the Washington Monument, moving in slow motion as a cloudscape flies by him implausibly fast, with Gandhi at the base of the podium reaching up to him.

This is ENO's third outing for this production since its debut in 2007 – and no wonder, when it combines an adventurous artistic vision with surefire commercial success in a way that director's opera so often doesn't – but I don't think it would be unjust to say that last night was more like a last rehearsal than a first performance. More than once a character failed to hit their mark, and had to shuffle awkwardly into the light that was intended for them. Moreover, the men's chorus, especially in the nightmarishly difficult "laughing chorus" of Act II Scene I, tended to rush ahead while the orchestra's repeated arpeggios if anything lagged slightly behind conductor Stuart Stratford. There were also tuning problems among the female soloists, especially Claire Eggington as Miss Schlesen and Janis Kelly as Mrs Naidoo. The ever reliable Nicholas Folwell made an excellent Kallenbach.

Alan Oke as Gandhi is on stage practically all the time, but has less to sing than that might imply. He had a worrying wobble in his voice in the opening scene, as if not quite warmed up, but this soon went and reminded us what a glorious voice he has for the role – tender and reflective or powerful as the situation demands – and his characterisation is remarkable, particularly when he's given so little to do physically to convey it. All in all, a glorious evening, and it's to be hoped that the few rough edges of this opening night can be ironed out for the rest of the run.

Satyagraha, at London ColiseumRoger Smith reviews English national Opera's performance of Philip Glass's Satyagraha at the London Coliseum.4