What does the exposition in the beginning of act one tell readers about the way they are to perceive the events that follow? explain?

You forgot to say what was the play that the question is referring to.

The question is referring to the play "The crucible".

Answer:

The beginning of the act in "The Crucible" shows that the reader that the whole narrative of the play will take place in a very puritan society, extremely religious and with limited thinking. It also shows that because of so much Puritanism the city where the play is established is governed by a set of very strict rules that dictate the appropriate behavior, and those that are different will be considered wrong and will be judged.

With that, we can understand that the events that will arise during the narrative, will cause a great hysteria and commotion in the city, because they are events that violate the rigid rules of this very limited society.