Dimmesdale's sermons throughout the novel are wrought with situational irony because he is calling on people to behave virtuously even though he himself has failed to do so. An early example of situational irony in Dimmesdale's sermons occurs in Chapter 3, when Dimmesdale tells Hester why she should reveal Pearl's father:
"Be not silent from any mistaken pity and tenderness for him; for, believe me, Hester, though he were to step down from a high place, and stand there beside thee, on thy pedestal of shame, yet better were it so than to hide a guilty heart through life."
Dimmesdale knows that he is Pearl's father. It is hypocritical for him to place a moral burden on Hester to reveal Pearl's father when he himself is "hiding a guilty heart through life." As the town minister, Dimmesdale ought to lead by example. At the very least, he ought to live up to the moral codes he imposes on others. The irony of the situation (Dimmesdale tells Hester and the town to do the opposite of what he is doing) emphasizes how all-consuming Dimmesdale finds his own shame to be. He cannot bring himself to reveal his identity, and so he pleads with Hester to do it for him. He therefore calls upon her to behave in the way that everyone would expect him to behave.
Although some Puritans in the novel (such as Governor Winthrop) seem to delude themselves about their own hypocrisy, Dimmesdale is keenly aware of his. In Chapter 11, he points out the irony that he has maintained his office as pastor through the entire scandal:
["]I, your pastor, whom you so reverence and trust, am utterly a pollution and a lie!”
The role of the pastor, according to Dimmesdale, commands "reverence and trust." He sees himself not only as unsuited to the role, but also as dangerous to its sanctity: he "pollutes" it. It is true that Dimmesdale is a liar, but it is important to note that what he calls himself is a "lie." The townspeople see him as their pastor, but he believes he is deceiving them. He does not deserve their reverence and trust, so he is not a real pastor. Instead, he is a wolf in sheep's clothing who threatens everyone's morality by passing himself off as a perfect Puritan.
There is situational irony in the fact that the government wants to separate Hester and Pearl from one another years after they have been exiled. In Chapter 7, the narrator criticizes the governor for getting involved in the scheme to take Pearl away from Hester, which is supposedly for both of their moral betterment:
Among those who promoted the design, Governor Bellingham was said to be one of the most busy. It may appear singular, and indeed, not a little ludicrous, that an affair of this kind, which, in later days, would have been referred to no higher jurisdiction than that of the selectmen of the town, should then have been a question publicly discussed, and on which statesmen of eminence took sides.
The irony at play here is that, after years of mistreatment, the townspeople have suddenly decided that they're concerned about Hester and Pearl's well-being. Hester and Pearl were both exiled from their community, and they haven't bothered anyone for years. In fact, they've been quite self-sufficient and have been living on the outskirts of town. The extent of their involvement in town affairs is that Hester sews clothing for people, and the pair is a perpetual target of gossip and bullying. It's absurd, then, that the very same locals who have never tried to help Hester and Pearl now want to separate them "for their own good," as if they actually care about them. It is obvious to the reader by this point that Hester and Pearl have a strong bond and that hardly anyone else has either of their best interests in mind. It seems more likely that the people who want to separate them simply want more material for the gossip mill and more reasons to feel morally superior.
Dimmesdale's declining health foreshadows his eventual death from a guilty conscience. One example of this foreshadowing occurs in a moment of dramatic irony in Chapter 8, when the narrator describes the townspeople's reaction to Chillingworth's interest in Dimmesdale:
It was understood that this learned man was the physician as well as friend of the young minister, whose health had severely suffered, of late, by his too unreserved self-sacrifice to the labors and duties of the pastoral relation.
Everyone assumes that the doctor takes an interest in the pastor because Dimmesdale's health is suffering. There is dramatic irony in this assumption because it is true, but not for the reasons the townspeople believe. Chillingworth is interested in Dimmesdale because his failing health signals to the doctor that he is hiding something. Chillingworth cozies up to the ailing man because he believes him to be Pearl's father. The fact that Dimmesdale's body shows the signs of his guilty conscience hints at the fact that in the end, a guilty conscience may just be able to destroy him.
Additionally significant to both the dramatic irony and the foreshadowing here is the townspeople's assumption that Dimmesdale's health is suffering because he is an overcommitted minister. They are not technically wrong that Dimmesdale's job is causing him to suffer. But his suffering isn't due to the fact that the job is too much of an administrative burden. Rather, his "labors and duties" cause him to sicken and eventually die because he cannot perform them in good conscience while he is hiding is own sinfulness. Neither Chillingworth nor the townspeople are entirely right or entirely wrong about the cause of Dimmesdale's ailment. His health problems and eventual death are the result of combined factors: he could have survived either his adultery with Hester or his job as a minister, but he can't deal with the ongoing tension between his public virtue and private sin.
Dimmesdale's sermons throughout the novel are wrought with situational irony because he is calling on people to behave virtuously even though he himself has failed to do so. An early example of situational irony in Dimmesdale's sermons occurs in Chapter 3, when Dimmesdale tells Hester why she should reveal Pearl's father:
"Be not silent from any mistaken pity and tenderness for him; for, believe me, Hester, though he were to step down from a high place, and stand there beside thee, on thy pedestal of shame, yet better were it so than to hide a guilty heart through life."
Dimmesdale knows that he is Pearl's father. It is hypocritical for him to place a moral burden on Hester to reveal Pearl's father when he himself is "hiding a guilty heart through life." As the town minister, Dimmesdale ought to lead by example. At the very least, he ought to live up to the moral codes he imposes on others. The irony of the situation (Dimmesdale tells Hester and the town to do the opposite of what he is doing) emphasizes how all-consuming Dimmesdale finds his own shame to be. He cannot bring himself to reveal his identity, and so he pleads with Hester to do it for him. He therefore calls upon her to behave in the way that everyone would expect him to behave.
Although some Puritans in the novel (such as Governor Winthrop) seem to delude themselves about their own hypocrisy, Dimmesdale is keenly aware of his. In Chapter 11, he points out the irony that he has maintained his office as pastor through the entire scandal:
["]I, your pastor, whom you so reverence and trust, am utterly a pollution and a lie!”
The role of the pastor, according to Dimmesdale, commands "reverence and trust." He sees himself not only as unsuited to the role, but also as dangerous to its sanctity: he "pollutes" it. It is true that Dimmesdale is a liar, but it is important to note that what he calls himself is a "lie." The townspeople see him as their pastor, but he believes he is deceiving them. He does not deserve their reverence and trust, so he is not a real pastor. Instead, he is a wolf in sheep's clothing who threatens everyone's morality by passing himself off as a perfect Puritan.
Dimmesdale and Chillingworth's relationship in the novel is built around dramatic irony: Chillingworth knows that Dimmesdale is Pearl's father, but Dimmesdale does not know that Chillingworth his Hester's estranged husband. In Chapter 14, Chillingworth tells Hester how this uneven knowledge has been impacting Dimmesdale:
"He knew, by some spiritual sense,—for the Creator never made another being so sensitive as this,—he knew that no friendly hand was pulling at his heart-strings, and that an eye was looking curiously into him, which sought only evil, and found it. But he knew not that the eye and hand were mine!"
Chillingworth tells Hester that he hasn't done anything to Dimmesdale and that, in fact, he has saved his life by keeping his own identity a secret. Still, Dimmesdale's health has been deteriorating on its own because he senses himself caught in some hostile "eye and hand." The dramatic irony, which Chillingworth notes is at play in their dynamic, almost seems to make Dimmesdale's torture more painful. The narrator has already revealed that Dimmesdale regularly inflicts pain on his own body as punishment for his sin. Chillingworth is right that Dimmesdale is sensitive: he is so sensitive, in fact, that he has turned his own "eye and hand" against himself. Dimmesdale is locked in his own head with his own shame, and Chillingworth withholds the chance for Dimmesdale to turn his "eye and hand" against an outside enemy. If Dimmesdale knew that he was engaged directly in a conflict with his doctor, Dimmesdale could not only fight off that opponent, but he could also release himself from the burden of keeping his adultery a secret. Chillingworth's relish in the dramatic irony underscores his role as a conniving villain who delights in psychological torture, even as he professes to have saved Dimmesdale's life.
Dramatic irony also adds to a sense of the occult in the novel. Does Dimmesdale somehow sense Chillingworth's identity, and is that contributing to his health problems? Hawthorne does not fully answer this question. It is entirely possible to interpret Dimmesdale's health problems as the result of his self-punishment and the extreme stress he feels to keep his sins a secret. But just as people sometimes sense a certain mystici sm about Pearl that might or might not be real, it is also possible to imagine that Dimmesdale's health is suffering from some sort of curse Chillingworth has placed on him. Within the world of the novel, Chillingworth's association with Indigenous medicine supports the possibility that something magical is afoot. Hawthorne and many other white people have long held racist ideas about Indigenous people and the occult. Hawthorne allows the reader to wonder whether Chillingworth's "captivity" transformed him into some kind of evil magician.