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.