In the first section, lines 1315-1339, we know that Oedipus' downfall is the result of his own fault and his own edict. He blinds himself and faces to be expelled to his country because of murdering his father. "If I had eyes, I do not know how I could hear the sight" (1317-1318). The word "sight" means the ability to see, and here it implies having the courage to face his people and his family. "How could I look men frankly in the eyes?"(1332). It is a visual image means he feels shameful to face this world, and figurative language is also used in this section to refer to Oedipus' sadness and compunction "A tight cell of misery, blank to light and sound:/ So I should have been safe in my dark mind / Beyond external evil" (1336-1338). He would rather stay along and become a blind man than expose to the public.
In the second section, lines 1340-1351, Oedipus states his committing and feels miserable about his birth. The word "cancerous" means malignant, and it implies his crime is serious and unforgivable. "For I am sick, / In my own being, sick in my origin" (1345-1346). It is a figurative language means Oedipus's wretched fate is destined and nobody can help or stop it. "O three roads, dark ravine, woodland and way / Where three roads met: you, drinking my father's blood," (1347-1348). It states a quite clear visual image where Oedipus kills his father.
In the third section, lines 1352-1361, the play shows although Oedipus loses his throne, his eyes and his family, he knows who he is. "Al, the net / of incest, mingling fathers, brothers, sons, / With brides, wives, mothers: the last evil" (1354-1356). Here the word "net" means the incestuous relationship; it also shows a visual image that nobody can bear this situation, and this is the reason why Oedipus blinds himself. "No. For the love of God, conceal me / Somewhere far from Thebes; or kill me; or hurl me / Into the sea, away from men's eyes for ever" (1357-1359). Eventually, Oedipus knows who he is, and realizes his committing and deserves the punishment.
Overall, we see that Oedipus is really a tragic hero, and the theme of the play is by using Tiresias' physical blindness to reveal Oedipus' mental blindness. What Oedipus does, what he says, and even who he is can sometimes be ironic. Many people in society today are blind to their past, and they don't know how the outcome of certain events affects them. Some of these people think that the only way to conquer this blindness is to seek out the truths of their past in order to lead a more fulfilled life.