Final answer:
Roger Chillingworth's invasive action while Dimmesdale sleeps symbolizes his obsessive quest for revenge and reveals his malevolent character in 'The Scarlet Letter'.
Step-by-step explanation:
The question pertains to the novel The Scarlet Letter by Nathaniel Hawthorne. When Reverend Dimmesdale sleeps, Roger Chillingworth, who is Dimmesdale's physician and Hester Prynne's estranged husband, secretly inspects the sleeping minister and discovers a mark on his chest. This action symbolizes Chillingworth's invasive and vengeful scrutiny of Dimmesdale's private guilt and torment over his sin. This incident reveals Chillingworth's obsession with revenge and his transformation into a figure representing evil and malice.