At the start of Act IV, Parris has been figuring out ways to remain relevant in the town's mindset. The dismissive responses from Danforth and Hathorne reflect how the trials have descended into madness.
When we first see Parris in Act IV, Hathorne describes him as having a "mad look" and has lost weight. Parris has come to see everything he once stood for as having fallen apart. Abigail has run away, stealing his money in the process. At the same time, he has become fearful of the rebellion from the people in neighboring towns regarding their witchcraft trials. Parris's life has also been threatened with a "dagger."
In the midst of all of these events, Parris has been working on a potential solution that can stem both the growing discontent with the trials and salvage what is left of his reputation. He proposes to both judges that they "postpone these hangin’s for a time." Parris believes that this approach would be the best for all of those involved. He recognizes that he might even gain credibility for proposing a suspension of the hangings and recover some of his damaged name.
Both judges are quick to rebuke this suggestion. Given how Hathorne describes Parris as "unsteady," he rejects his suggestion. Danforth is equally forceful as he argues that a postponement would vitiate the word of the court. He believes that he can manipulate a confession out of the prisoners who are awaiting execution. However, it is clear that Parris' hopes are dashed through Danforth's and Hathorne's insistence that their court rulings override all other considerations.