Tartuffe enters, and upon seeing Dorine, calls offstage for his “hair-shirt” and “scourge”—tools that particularly religious men would use to harm their own bodies as a way to repent for their sins. He then announces his intent to go to the prison and share his “last few coins with the poor wretches there.” Dorine, in an aside, rolls her eyes at Tartuffe’s ostentatious display of piety; she knows that he is a “fake.”
After two acts and a scene of building anticipation, Tartuffe finally comes on stage. And he doesn’t disappoint: notice that his pious act begins only when he sees that Dorine is there, too. Dorine, of course sees through him. It is worth noting that Tartuffe’s hypocrisy is different from those of Orgon and Pernelle. Those two are hypocrites based on their self-importance and blindness; they don’t even realize they are hypocrites. Tartuffe is a purposeful hypocrite, saying one thing and doing another to try to get what he wants.
Tartuffe gives Dorine a handkerchief and urges her to cover her chest with it lest she inspire impure thoughts. Dorine replies that his piety must be very weak if even the sight of her excites him—even if she saw him “naked as a beast,” she says, she would not feel tempted by him.
Once again the pious blame others for inciting their own impious thoughts (though of course here there is another layer as Tartuffe is only pretending to be pious). Ever the trickster, Dorine uses Tartuffe’s exaggerated show of modesty in order to mock and insult him.
Insulted, Tartuffe tells Dorine that he will leave, but when Dorine tells him that Elmire is on her way to talk with him, Tartuffe immediately replies that he will stay. As Elmire enters, Dorine exits, commenting that her guess about Tartuffe’s fondness for Elmire must be correct.
The moment that Tartuffe hears Elmire’s name, his pretense of modesty vanishes. Piety means nothing to Tartuffe when it stands in the way of something he wants (in this case Elmire).