In Act 4 of "The Crucible," Sarah Good's exclamation about "His Majesty" coming reflects her desperate state and her mental instability as she faces execution. By referring to the "Majesty" (which can be interpreted as God or a higher power), she may be expressing a distorted hope or a last-ditch grasp at understanding her fate. In the context of the play, the impending hangings drive the characters to different forms of madness and hysteria, and Sarah Good's outburst exemplifies her fear and confusion as she confronts the reality of her situation.
Additionally, Sarah Good's statement can be seen as an ironic twist, as the term "majesty" typically refers to authority, which in this case serves to underscore the absence of true justice in the court. The "majesty" she believes she is calling upon is not the compassionate divine entity, but rather the corrupt power structures that have condemned her and others unjustly.
Overall, her declaration adds to the themes of fear, hysteria, and the quest for redemption in a society mired in paranoia and moral ambiguity.