Climax functions in a plot as the point of highest tension and is the point at which a character changes his point of view.
In Sophocles's play, filled with hubris, Oedipus the king of Thebes, is, as the sightless seer Teiresias tells him, blinder than he,
But I say that you, with your both eyes, are blind:
You cannot see the wretchedness of your life
For, Oedipus accuses Teiresias of being a madman and Creon of desiring the throne. However, because he is of noble nature, Oedipus yet pursues the truth until, after speaking with Jocaste in Antistrophe 2, he says, "I am not sure that the blind man can not see." This, then, is the point at which Oedipus changes his point of view; from this point he begins to put things together and declares that he has reached a "pitch of wild foreboding."
Oedipus Rex is a play that revolves around the king's search for knowledge. Thus, the climax comes at the point in which Oedipus recognizes the truth. And, because of his noble nature, Oedipus keeps his promise to the people of Thebes and pursues the truth.
If climax in a play is seen as the point in which there is the highest amount of tension, I think that the final act in Sophocles' drama marks the climax. It is at this point where the tension reaches its zenith. The truth has been revealed. Oedipus, the Chorus, and all the citizens of Thebes understand the true nature of what has been around them. Oedipus blinds himself upon hearing the news of the suicide of his mother/ wife. Oedipus' forceful recognition of this truth as well as the act of blinding himself represents the climax. It was to this point towards which the drama had been hurdling. Oedipus feels the crushing weight of fate and understands the futility of his own freedom in the face of such larger elements. This would have to be the climax because it is at this point where all questions are answered. It is at this point in which there is the greatest tension. The news of what Jocasta has done and what it means is what hits Oedipus with the greatest of force. The climax presents itself here as the culmination of the previous acts. They have led to this emotionally raw and intense moment. The powerful reality of self- recognition and the lucidity of seeing one's own predicament in a larger element is where the climax in Sophocles' drama is illuminated.