Contrast the play The Importance of Being Earnest with the 2002 film.
In many films based upon written works, while the basic plot, major characters, style, and prominent themes are developed, the minor characters are often either ignored or only given cursory treatment. This is true in the 2002 film version of The Importance of Being Earnest as well, even though the omissions could be simply because of time limitations.
In the film version of Wilde's play, the characters of Miss Prism and the Reverend Chausible are presented merely as flat, comical personages. However, in the play, these two characters are tools of Wilde's more subtle satire on Victorian self-righteous behavior and religious hypocrisy. Certainly, their names are clues to these satiric depictions.
Interestingly, Miss Prism's name refers to a glass that is many-sided. If one looks through a prism, he or she obtains a different view from the reality. With this name, then, Wilde satirizes the Victorians' narrow-mindedness and hypocrisy. For Miss Prism, the tutor who often corrects Cecily's behavior, is certainly not one to be justifiably doing so since her own past behavior has been far more "improper." (She left Jack in a handbag at Victoria Station years ago.)
The Reverend Chausible is portrayed in the film as a farcical character, and the only religious satire that might be suggested is the pastor's surreptitious glancing at salacious pictures in magazines or books that he quickly hides when someone catches him in the act. Whereas the Reverend is a flat character in the film, in Wilde's play he is more developed, as he hypocritically finds a way to work a sermon into any context for his own advantage. Further, his name suggests Wilde's satiric attitude toward Anglicanism or Catholicism, as the nomenclature mocks the respected exterior vestment worn at the Mass. The minister's ineptness also satirizes the authority traditionally given to the Church.
Personally, I really enjoyed Parker's take on the play. The actual differences were in the interpretations behind the scenes. Cecily is so hopelessly romantic that she is constantly in a dream state with the knight in shining armor. Also, Jack and Gwendolyn get tattoos--this is quite amusing in our time period, but nothing like that would have occurred. It helped create more irony in the end when Gwendolyn finds that he truly is Ernest.
However, on a more cynical yet realistic note, the real focus of the play should have been on Lady Bracknell. Instead, it was focused on both of the bachelors and their lives. Wilde used Lady Bracknell to express his frustration with the Victorian era, and Lady Bracknell was the figure who represented all of absurdity of the time period. She should have been the focus, and yet Parker had her play the controlling matriarch instead of a pompous and almost idiotic character. The reason for Parker to create the movie in this light was most likely to keep up with the romantic comedies that take up so much of the movies that are presented to us every day.