Can you please explain what Miller's narrative regarding Reverend Hale is all about (act 1)?

In act I of The Crucible, Reverend Hale is presented as conscientious in his duty as a witch-hunter. He arrives in Salem determined to get to the bottom of the rapidly developing witch-craze. And it's clear right from the outset that Hale is very much an idealist who genuinely wants the witch-trials to uncover the truth.
Although he believes in the existence of witches as much as anyone, Hale wants to make sure that only the truly guilty are punished for their misdeeds. In this, he is completely at odds with the likes of Parris, whose motives in participating in the witch-trials are far from pure. Whereas Parris has no hesitation in making false accusations against innocent people, Hale understands the importance of correct protocol. He never forgets that the trials are a legal procedure and, as such, should always involve due process. Hale's firm grounding in the law, combined with his relentlessly logical nature, allow him to remain calm amidst all the chaos and hysteria swirling around him. His presence reminds us of the overriding importance of doing justice in all cases, however serious the charges may be.