The prevailing tone of Hawthorne's The Scarlet Letter is one of irony. Here are some examples:
The Puritans, who have escaped religious persecution in England, first build a prison on their settlement. This prison and the scaffold are sites where people are persecuted and castigated for their sins. It is ironic that public condemnation is considered reliable by the Puritans.
The Reverend Arthur Dimmesdale, who is perceived as "ethereal" is as grievous a sinner as Hester Prynne who is sent to prison and made to stand upon the scaffold in ignominy, scorned by the viewers and later ostracized from society as she lives on the edge of the woods. However, the Puritan community exalt Dimmesdale as a saint while he is a terrible hypocrite in reality.
The governor of the settlement, Bellingham, has a sister who is a witch, yet no one objects to her activities. In addition, the leader of the Puritans, whose ideology holds to simplicity, has a beautiful mansion complete with diamond-like glass windows, suits of armor, pewter tankards with the remnants of beer visible, elaborately carved furniture, and a serving-man who wears a blue coat, the "customary garb ...in the old hereditary halls of England." That the leader of the community has these beautiful objects and enjoys a draft of beer points to the hypocrisy of those who would deny gaiety and passion to their community.
The punishment of Hester, the wearing of the scarlet letter, changes to a symbol of her ability and her solicitiousness to the community as nurse to the ill and dying. Thus, the meaning of the scarlet A changes ironically to Able and Angel.
Roger Chillingworth who agrees to treat Dimmesdale's apparent physical illness--which is ironically not a physical ailment--is really the minister's torturer.
In Chapter III, Governor Bellingham tells Dimmesdale, "...the responsibility of this woman's soul lies greatly with you."
In Chapter IV, Chillingworth tells Hester, "Think not that I shall interfere with heaven's own method of retribution." Yet, he intends to violate the secrets of the minister's heart and destroy him.
The readers discover long before the townspeople that Pearl is the child of the Reverend Arthur Dimmesdale and Hester Prynne.