Hester stands at the foot of the scaffold during the sermon since the rest of the town deem it inappropriate for an adulteress to sit among them in the church. That Hester is standing beside the same scaffold on which she was originally condemned before the entire community shows that she is still solely defined by her sin among the Puritan townspeople and leaders. She is still an outcast.

At this point, Hester and Dimmesdale are seeking to run away from their shame by taking Pearl and going away to a place where no one knows of their sin. They do this instead of redeeming themselves and moving beyond their adultery, which makes Hester's still standing beside the scaffold take on further meaning. It not only reflects her position in the community, but how she is actually taking a step back in her spiritual progression as well. By running away from her problems, she is still letting herself be defined by them instead of moving forward.

During this scene, she learns that Chillingworth knows of her and Dimmesdale's plans to run away together. Ironically, Dimmesdale seemed more "vigorous" during the procession, and this new development bodes ill for the lovers.

In Chapter XXII of "The Scarlet Letter" as the Rev. Dimmesdale begins his "discourse," Hester, feeling an irresistible pull, remains close, taking her position close beside the scaffold of the pillory because the crowd will not permit her entering the church.  She is close enough that she hears the ministers voice in a "varied murmur and flow" (this reminds the reader of the melancholic brook in Chapter XVI).  Hester listens so intently that the sermon has a meaning for her that transcends the words. She hears Dimmesdale's "plaintiveness" and expressions of anguish, of "suffering humanity."  Hester, standing statue-like at the foot of the scaffold, senses Dimmesdale's heart telling its secret as well as feeling a magnetic pull to the place of her initial ignominy.  Pearl, full of nervous energy, plays around the marketplace.  But, Hester, feels now that her life, before and after this moment, is connected with the spot where she stands.