My 2¢Does anybody consider Classical Music Pieces with dark or alternative subject matter offensive to persons with a strong religious faith. The pieces listed below are just some I singled out, there are countless others that could be added as well.
Richard Strauss: Also Sprach Zarathustra / Alpine Symphony / Death and Transfiguration / Salome: Dance of the Seven Veils
Igor Stravinsky: Rite of Spring
Hector Berlioz: Symphonie Fantastique
Camille Saint-Saëns: Danse Macabre / Bacchanale from Samson and Delilah
Modest Mussorgsky: Pictures at an Exhibition / A Night on the Bare Mountain
Gustav Holst: The Planets
Sergei Rachmaninov-The Isle of the Dead and Countless other pieces.
The pieces above are all instrumental, except the wordless vocals on Holst:Neptune, and I do not listen to them with a program. Meaning, that anything the composer may or may not have intended to be associated with the piece is lost upon me. I have my own thoughts while listening to any piece of music. Being a devout music lover, I have often wondered about this matter with several music pieces, but I have found no general consensus regarding this matter.
Instrumental music is only "offensive to persons with a strong religious faith" if they so choose to associate that instrumental music to something they find religiously offensive.
I'd go so far to say that there IS a "general consensus" that instrumental music of the sort you've listed is inoffensive.