Carl Maria von Weber, the early-19th-century German composer, wrote ten or so operas. But we know basically three of them, and those chiefly through their overtures, and a few arias. The operas I’m speaking of are “Der Freischütz,” “Euryanthe,” and “Oberon.” The Salzburg Festival is performing the service of staging “Der Freischütz” this year. But it is staging it in a production that baldly subverts the opera — thereby canceling the service.

“Der Freischütz” means “The Marksman,” roughly, and it is a “singspiel” — an opera that combines singing and talking. It is a cousin of “The Abduction from the Seraglio” and “The Magic Flute,” both by Mozart. The story is a Faustian one concerning a man who sells — or almost sells — his soul to the devil. He is rescued in the end, by the overwhelming force of good. This is a Christian tale.

But how do you handle a Christian tale on a continent whose elite culture is decidedly post-Christian, to say the least? More about that in a moment.

“Der Freischütz” has a famous, wonderful overture, and, on Monday night, the Vienna Philharmonic botched it. Or rather, disappointed in it. Under Markus Stenz, a German conductor, they were weak, sloppy, and unspirited. Has the VPO been working too hard, in this ultra-demanding festival? The overture was partially redeemed by a first-class clarinet solo. But still, the Utah Symphony would have been embarrassed to play the overture this way.

Thereafter, the orchestra performed decently, with some terrific French-horn work — where you have huntsmen, you have horns — and some fine cello solos. But the mighty Vienna Philharmonic did not cover itself in glory on this night.

In the central role of Max was a German tenor, Peter Seiffert. He was generally heroic, and musically aware. But his sound was slightly pinched, and his lower register — which gets a workout in this opera — lacked oomph. The role of Agathe was sung by Petra Maria Schnitzer, an Austrian soprano. She was occasionally uncertain, but she seemed to gain confidence as the evening wore on. In the beloved aria “Leise, leise,” she did not show great beauty of sound, and did not evince much power. But she was sincere, which counts for a lot.

The Canadian bass-baritone John Relyea portrayed Kaspar, one of the villains of the piece. Mr. Relyea was convincing in his acting — sometimes scalding — and faultless in his singing. Indeed, he is one of the most reliable singers in opera (or oratorio or recital). A young Polish soprano, Aleksandra Kurzak, was Ännchen, and she sang pleasantly. Once or twice, she sang beguilingly.

An Austrian bass-baritone, Markus Butter, did a good job as Ottokar, and Günther Groissböck did a good job as well. Mr. Groissböck is an Austrian bass, and he sang the Hermit — the holy character who comes on at the end and declares redemption. Note, too, that the Chorus of the Vienna State Opera sang splendidly all through.

There is a purely theatrical role in this opera, and it is Samiel, the devil figure. He was played by Ignaz Kirchner, a German actor, and played brilliantly. Mr. Kirchner did not ham it up, but neither was he shy — he was pitch-perfect. His Samiel was like a Vegas emcee, evilly grinning in a white suit.

Salzburg’s production is in the care of Falk Richter, a director from Hamburg. When the curtain opens, we behold the chorus — the townspeople — as a bunch of fatsos, dressed in vulgar clothing: shorts, jerseys, and T-shirts. Many of them have cameras or binoculars around their necks. One of the fatties has a T-shirt with the American flag on it. Your modern European stage director is not known for subtlety.

Before long, all of these people sit down and simultaneously take out bags of greasy snacks, which they eat noisily. What was I saying about subtlety?

Naturally, the production is full of sexual moves, including some feigned ejaculation, which we all thought was cool in junior high school. But this isn’t junior high school: It is the Salzburg Festival.

In the course of the opera, Mr. Richter uses a lot of film, and some of this use is effective. And this must be said for him, too: He leaves Agathe’s arias — tender and heartfelt — alone. That is, he lets her sing them unmolested, without sabotage, which may get him kicked out of the Directors’ Guild.

At the end of Act II, we have some hot nude models, parading around in high heels. They kneel down to take communion, in a kind of black mass. And the characters now and then leave German for English, speaking words we don’t exactly expect in “Der Freischütz.” One of Samiel’s acolytes declares, “Money is everything.” And John Relyea’s Kaspar speaks some of the pivotal words of the opera — Mr. Richter’s opera, that is:

“Destruction, death, corruption, rape, war, invasion, burnt children, low taxes, and religion — that is what we would kill for; that is what our hearts yearn for.”

Yes, low taxes, to go with burned children and religion. It crosses my mind that Mr. Relyea should be ashamed to aid and abet this despicable show. John F. Kennedy (a low-tax man, incidentally) said, “Sometimes party loyalty asks too much.” Well, does an opera career ever ask too much?

This production is like a parody of the modern European director’s vision of “Der Freischütz,” and of the world. The Hermit is not a hermit, but a televangelist, disgusting in his silver and gold outfit, complete with large, gaudy diamond cross. The Hermit of the real “Freischütz” is a figure of relief and mercy; the Hermit of Mr. Richter’s “Freischütz” is a figure of obscenity and mockery.

In a final act of subversion, Mr. Richter has Samiel’s helpers take blood from sacramental chalices and daub four English words on the wall: “In God We Trust.” Subtle, subtle, subtle. The main character, Max, looks on these words with fear and wonder. Instead of being saved, he is cast into doubt.

Look, not every director or company wants to put on a Christian opera, and that is perfectly understandable. But if you feel that way — leave “Der Freischütz” alone. There are plenty of other operas to choose from. Why brutalize Weber?

One of the tragedies here is that Mr. Richter is evidently a talented and skillful man. He has simply been engulfed by the ideology and superstition of the culture around him. He and his colleagues love to cry against America and Judeo-Christian civilization, and they do so to much applause. One can only wish them luck under Sharia.