In Act I, Madame Pernelle, who uses stereotypes to characterize everyone around her as a "fool," "perfect rake," "nothing but a plague" and platitudes such as "still waters...are the deepest," declares that Tartuffe is not the hypocrite that Dorine calls him;instead she asserts, he "tells you the naked truth" and he is "a good man." Further, she declares, that her son never acted more wisely than when he invited "this devout man" into his home.
Like his mother, Orgon is close-minded and easily duped. He, too, refuses to listen to Dorine. When Cleante, Orgon's son complains of the "heat" Mme. Pernelle has been in and how fond she is of Tartuffe, Dorine adds that Orgon is as equally duped,
"...this is nothing compared to the infatuation of her son...He calls him [Tartuffe] brother...He's the only confidant of all his secrets, and the wise director of all his actions; He will have him seated at the upper end of the table...."
In Act II, when Dorine tries to talk him out of forcing his daughter to marry Tartuffe, whom she suggests wants Orgon's money, she asks him,
"For what reason would you go, with all your wealth, to choose a beggar for a son-in-law?"
like his mother, Orgon silences Dorine,
"Hold your tongue! If he has nothing, know that we ought to esteem him for it.
Even when his wife Elmire informs Orgon of Tartuffe's lascivious advances upon her, Orgon refuses to believe her until he is hidden under the table and overhears Tartuffe.