At the time that the reader comes across this passage, the Reverend Mr. Dimmesdale just completed his conversation with Hester in the forest. In this conversation, Hester and the Reverend discuss what the future holds for the two of them and a possible exit from the town. To the reader, one can see that this plan will fail and that these two can never be together. In the Reverend's case, he can not see this, but rather he sees the optimistic future which Hester and he had discussed. Dealing with guilt and the difference between Nature and Civilization, two themes in this novel, are dealt with in this passage. Through the use of an extended metaphor in this passage, as well as in many other passages, Hawthorne informs his reader of major plot themes and issues to be considered.
"The excitement of Mr. Dimmesdale's feelings as he returned from his interview with Hester, lent him unaccustomed physical energy, and hurried him townward at a rapid pace. The pathway among the woods seemed wilder, more uncouth with its rude natural obstacles, and less trodden by the foot of man, than he remembered it on his outward journey. But he leaped across the plashy places, thrust himself through the clinging underbrush, climbed the ascent, plunged into the hollow, and overcame, in short, all the difficulties of the track, with an unweariable activity that astonished him. He could not but recall how feebly, and with what frequent pauses for breath he had toiled over the same ground, only two days before." .
Throughout this story, the character of Reverend Mr. Dimmesdale possesses a weak and feeble personality, but in this passage, immediately following his conversation in the woods with Hester, Mr. Dimmesdale acts completely out of character, "leap[ing] across the plashy places," and using "unaccustomed physical energy." In this passage, he appears to be an embodiment of his former self, before he and Hester committed their sin.