How does Dimsdale react to Chillingworth? Why?

Dimmesdale is bent on punishing himself. complements his emotional masochism with physical masochism. He fasts, flagellates himself, and keeps waking vigils so that he deprives himself of sleep, all in the hopes of banishing sin from his heart. He accommodates Chillingworth because Chillingworth has become part of his punishment. Dimmesdale had to know this guy was evil, I think he accepted Chillingworth as part of his penance.