During the first half of Sophocles' Oedipus the King, Oedipus is faced with discovering who killed Laius, the previous king of Thebes. To solve this mystery, Oedipus seeks advice from the chorus of Theban elders. They suggest that Oedipus consult with the Theban prophet Teiresias. They describe him as a man who "can see into things" with a skill comparable to that of the prophetic god Apollo. The Chorus Leader goes on to say that consulting a person like this might lead him to find out who killed Laius. Oedipus tells the Theban elders that he has, indeed, summoned Teiresias.
Additionally, just before Teiresias arrives, the Chorus Leader describes the prophet as "god-like" and says that in Teiresias "the truth resides / more so than in all other men" (Ian Johnston translation).
Comments like this from the Chorus Leader raise the audience's expectation that Teiresias' prophetic skills are on a par with the god Apollo. Sophocles' Athenian audience is also led to believe that what Teiresias says will be the truth.