In Chapter XXIV, "Conclusion," Hawthorne intrudes into his narrative and states his prevailing theme:
—“Be true! Be true! Be true! Show freely to the world, if not your worst, yet some trait whereby the worst may be inferred!”
That it is the hypocrisy of secret sin which destroys the person is demonstrated with Hawthorne's characterization of the Reverend Dimmesdale and Roger Chillingworth, who each harbor a debilitating sin in their hearts. In fact, Chillingworth himself comments upon the effect that the spiritual state has upon the corporeal in Chapter X in his conversation with Dimmesdale. He tells the minister that the dark "unsightly plants" that he has gathered are from an unmarked grave:
"They grew out of his hart, and typify, it may be, some hideous secret that was buried with him, and which he had done better to confess during his lifetime."
"Perchance," said Mr. Dimmesdale, "he earnestly desired it, but could not."
“And wherefore?” rejoined the physician. “Wherefore not; since all the powers of nature call so earnestly for the confession of sin, that these black weeds have sprung up out of a buried heart, to make manifest an outspoken crime?"
Chillingworth, then, points to Hester as an example of his point,
There goes a woman,” resumed Roger Chillingworth, after a pause, “who, be her demerits what they may, hath none of that mystery of hidden sinfulness which you deem so grievous to be borne. Is Hester Prynne the less miserable, think you, for that scarlet letter on her breast?”
Truly, Hester finds a certain freedom from the overt display of her sin that sharply contrasts with the tortures of the hidden sin of adultery in the heart of Dimmesdale as well as Chillingworth's covert sin of the violation of the secrets of a man's heart. Little Pearl, the incarnation of Hester's sin is also proof of this truth as Dimmesdale acknowledges when he says that she has "the freedom of a broken law." But, Chillingworth and Dimmesdale deteriorate physically because of the corruption of their souls. For, Chillingworth himself tells Hester that he has become a "fiend"; Dimmesdale's conscience is constantly tortured as his congregation believes him saintly, and he must deceive them. In Chapter XX, Hawthorne writes,
No man, for any considerable period, can wear one face to himself, and another to the multitude, without finally getting bewildered as to which may be the true.
It is this bewilderment, this torture of conscience, that is devastating to the body of both the Reverend Dimmesdale and Roger Chillingworth. Hypocrisy, borne of secret sin, is what destroys these men. Only Hester is able to return to the Puritan community.