Jocasta finds out that Oedipus' adoptive father died and doesn't tell Oedipus, the citizen of Corinth comes to Thebes to tell Oedipus of his adoptive father's death and also tell him he needs to become king. The audience should feel pity for him.
Oedipus worries about Merope because of the prophecy. The audience should sense irony because we already know Merope isn't his real mom.
Oh no mom!
The citizen tells Oedipus that he's not Polybus' son. The audience should feel sadness for Oedipus because he keeps trying to deny it and doesn't believe it's true.
Jocasta tells Oedipus not to dig any further into his identity because she realizes the truth. The audience should feel suspense because we don't know what Oedipus will do now.
Oedipus and Jocasta found and spoke to one of Laius' workers, Laius' man said he gave Oedipus to the citizen of Corinth to raise him. The audience should feel shocked for Oedipus because he now knows he wasn't raised by his parents and was lied to all his life.
Oedipus now has realized that he was abandoned by his parents and given to a new family whom he believed was his biological parents. He also now realizes the man he murdered was his father and the woman he married was his mother. The audience should feel relief that he now knows the truth about his life.
"All wrong in parents, those with whom I lived and him I murdered, wrong, all wrong!"