Why does Dimmesdale go back to the scaffold? What do you think brought him to this point? What is symbolic about the three characters standing on the platform together?

Dimmesdale begins to understand that he must himself embrace a figurative scarlet letter on his own breast. As a result, Dimmesdale ventures to the scaffold at night, perhaps unconsciously seeking absolution. Perhaps he believes that if he stands in the same place Hester did, he can find some degree of peace without having to publicly confess. But it is not enough. Dimmesdale already knows of his own guilt and susceptibility to sin. Perhaps Pearl recognizes this, for she urges Dimmesdale to stand beside her and her mother at noontime the next day on the scaffold. Pearl senses that things have come to a head, that Dimmesdale will soon confess and that there will be a reckoning for him that will set them all free. Dimmesdale demurs, perhaps knowing that he cannot bear to make such a confession, and instead suggests that he and Hester will find freedom in the dark. It is then that the meteor streaks by, illuminating them in the whitest of light, foreshadowing Dimmesdale's revelation to the town and, more importantly, the absolution that will come with confession.