The character of Tartuffe in Molière's Christian play Tartuffe is the prime example of deceit and deception. He passes himself off as a pious and religious man who is occupied with giving charity to the poor and, in this guise, gives moral instruction to all the household member's of his host's family. Under cover of this deceit and deception, Tartuffe is in actuality attempting to seduce the wife of his dearest friend and carrying on criminal activity.
Molière brands Tartuffe as a hypocrite in the play. In contemporary society, the word "hypocrite" has lost most of its stinging meaning but, in previous eras, the accusation of being a hypocrite was a serious religious charge. Easton's 1897 Bible Dictionary, quoted on Dictionary.com, may put the matter in perspective:
Hypocrite: one who puts on a mask and feigns himself to be what he is not; a dissembler in religion. Our Lord severely rebuked the scribes and Pharisees for their hypocrisy (Matt. 6:2, 5, 16). "The hypocrite's hope shall perish" (Job 8:13). The Hebrew word here rendered "hypocrite" rather means the "godless" or "profane," as it is rendered in Jer. 23:11, i.e., polluted with crimes.
Therefore that Molière brands Tartuffe as a hypocrite and contrasts Tartuffe to Cléante and the true Christian values he lives by is a significant matter of great seriousness, particularly so since it is abundantly clear from Tartuffe's behavior and activities that the one and only thing he wants to promote is his own personal agenda of amassing wealth, possessions, and social esteem--all come by wrongly.