When questioned further by Oedipus, the shepherd clarifies his account of Mount Cithaeron. Although he delivered Oedipus to Corinth, a different shepherd, a servant of King Laius, was the first person to discover the child. The king asks the Chorus for help in locating this herdsmen, asserting, The time has come to reveal this once for all.
Though Jocasta implores her husband to call off the investigation, Oedipus is paranoid to learn the truth. When Jocasta, who seems to sense the impending doom, realizes that Oedipus will keep probing, she is heartbroken and flees back into the palace.
Soon the old shepherd, the former servant to Laius, is seen approaching as beckoned. Though the old man wants to keep secret Oedipus' origin, he is finally forced to speak when the king threatens him with death. After he testifies, the mystery is finally solved-indeed this shepherd did pick up Oedipus as an infant. When questioned about where the baby came from, the shepherd admits that it was Jocasta who had given instructions for her child to be killed. She was afraid-frightening prophecies, he explains.
This causes Oedipus to speak this famous quote: O god-all come true, all burst to light! O light-now let me look my last on you! I stand revealed at last-cursed in my birth, cursed in marriage, cursed in the lives I cut down with these hands!
Soon the Chorus takes the stage, lamenting the tragic fate of their fallen king. Though they pity Oedipus, at the same time they realize that he has largely brought this agony upon himself. Though he cannot control his fate, his arrogant attitude and pompous actions seem at least to partially justify the internal torture he now feels.