On Friday night, “Satyagraha” came to the Metropolitan Opera. This is the work by Philip Glass composed in the late 1970s. The title is Sanskrit, and it can be translated as “The Firmness of Truth.” In fact, the libretto itself is in Sanskrit drawn from the “Bhagavad Gita.” The opera has a subtitle, too: “M.K. Gandhi in South Africa.” The opera is meant to depict the political, philosophical, and spiritual development of this extraordinary figure, Gandhi.

Mr. Glass’s score is a perfect example of minimalism. And you know this style, its strengths and weaknesses. At its best, minimalism is lulling, hypnotic, transporting. At its worst, it is maddeningly dull. The listener hopes to surrender to a minimalist score. If he can, he is happy — even “blissed out.” If he cannot, he is miserable and trapped. The musical drug has to take effect. If it does not, woe to the listener.

In my view, “Satyagraha” reflects minimalism both high and low — but mainly high. For me, the drug really takes effect in the second of the three acts. Mr. Glass’s music is inspired, skillful, and surpassingly beautiful. But — again, for me — the drug wears off in the third act, which succumbs to tedium. There is no complaining about the ending, however: Here we get an aria, or type of aria, sung by the tenor portraying Gandhi. It is a simple thing in C major; the tenor sings a simple ascending scale, E to E. Mr. Glass hit on something very nice here.

Is “Satyagraha” really an opera? Or is it more like an oratorio or cantata, with a production around it? There is certainly a sense of ceremony about this work. It has an air of churchliness, dare I say. (Templeness?) And a cynic may find it culty and naïve, not to mention pretentious. But there is a less cynical, and better, view.

Mr. Glass is certainly fortunate in this current production, and in his performers. The Met shares the production with the English National Opera. It is the handiwork of Phelim McDermott, director, and Julian Crouch, associate director and set designer. Like the score, the production contains considerable beauty and wisdom. When it is really succeeding, it is weird and wondrous. Otherwise, it is perhaps just weird.

Toward the back of the stage is a semicircular wall. Sometimes people peek out of windows in this wall. This peekaboo effect is used in opera productions all around the world. Onto Mr. Crouch’s wall, translations of the text are projected. There is no need for the Met’s nifty “seatback” titles, in this show. In any case, the words are few and repeated, in conformity with the notes.

Often, the meaning of what is happening onstage is unclear. But the stage is almost always interesting and pleasant to look at. An army of hangers descends from the sky; then up it goes, bearing clothes. Some people fly through the air, too. And other people are on stilts. When the production was at its silliest, I inevitably thought of the phrase “nonsense on stilts.”

Puppets appear: huge, grotesque, and engrossing. There is lots of playing around with newsprint — rolls and rolls of newsprint. (Gandhi is spreading the word.) There are rolls and rolls of clear packing tape, too. They are unspooled by people walking slowly across the stage. One person got stuck in this sticky stuff — a peril of the production.

The third act is titled “King” — a reference to Martin Luther King Jr., a disciple, of course, of Gandhi. We see video clips of American civil-rights protests. And a silent actor plays King, orating with his back to us (as in a famous photo from the Lincoln Memorial). The director may slightly overplay this theme: There is a line between due admiration and unseemly glorification.

Heading the cast is Richard Croft, singing Gandhi. He is one of the finest lyric tenors of our time. He is also strangely unsung (except by aficionados). His brother Dwayne, a fine baritone, is better known at the Metropolitan Opera. But Richard has had a steady and globetrotting career. He is pretty much unbeatable in Handel and Mozart. And he may be modest by nature (although not modestly talented). Faced with wild applause on Friday night, he would barely bow, eager to join his castmates in the line.

The part of Gandhi tests the middle and lower registers of a tenor’s range, and Mr. Croft’s were not found wanting. And his higher notes were exemplary. In addition, Mr. Croft has the ability to sing in a fashion both lyrical and clarion. That is a rare and valuable trick.

Across the board, the Met’s cast was capable and confident. Rachelle Durkin, a soprano, sang in bold, rich, and soaring lines. A mezzo-soprano, Mary Phillips, was slightly tremulous, but enjoyably potent.

And the conductor did a competent, professional job. It is a special challenge to conduct two and a half hours of minimalism. Our maestro was an Argentinian with a beautiful Italian name: Dante Anzolini. He kept the proceedings essentially together, and showed true commitment. For an orchestra, minimalism is an invitation to carpal tunnel — sustained repetition is a bear. But the Met’s orchestra sailed through. And its chorus sang with discipline.

We owe this to the minimalists, if nothing else: At a time when beauty in music was under attack — vilified as a bourgeois indulgence — they stood up for it.

And our debt to Gandhi is obvious. His example continues to inspire. Right now, there is a brave man, Oscar Biscet, in a Cuban dungeon. He is an Afro-Cuban physician and a democracy leader. He is a disciple of Gandhi and King. For years, he has been tortured and isolated. But, last year, President Bush awarded him the Medal of Freedom. Perhaps Dr. Biscet will one day be free to accept it in person.