While Hester Prynne is the protagonist of The Scarlet Letter, the character of Arthur Dimmesdale is in many ways more interesting and complex. Hester pays continually for having committed the sin of adultery, as she visibly displays the scarlet A on her clothes. She not only accepts the necessity for shame and atonement, but also finds comfort and delight in her sweet daughter, Pearl. Dimmesdale, however, does not publicly acknowledge his role. Rather than admit that he committed a sin, he maintains silence. Even worse, he represents himself as a pious, righteous man, and allows the townspeople to admire him as a role model of moral rectitude.
The burden of living a lie eventually becomes too heavy, however. At the end of the novel, his suffering is represented by a corresponding scarlet A—but this one is burned into his very flesh. Before that dramatic reveal, Dimmesdale passes through several steps that ultimately bring him to public confession. His declining physical condition, as he becomes thin and pale, even ghostly, parallels the decline in his spiritual well-being. A semi-public admission of sin, when he thinks no one is around to hear him, leads him to reconnect with Hester.
It turns out that the scheme they concoct to run away is no solution. They cannot run from their past, especially since Pearl is the all-too-real result. Rather than the initial sin of adultery destroying him, it was lying that took such a harsh toll. Hawthorne uses Dimmesdale to call attention to the hypocrisy of Puritan society, including its preachers.