We especially see the motif concerning sight and blindness in the dialogue between Oedipus and Tiresias. Tiresias is ironically a blind soothsayer or "seer." However, when Tiresias accurately prophecies that Oedipus is the "unholy polluter" of Thebes, meaning the one who committed the murder that is causing the plague, Oedipus disbelieves that he is speaking the truth (372). Instead, Oedipus proclaims that Tiresias does not have the truth due to his blindness, as we see in his line, "Since you are blind in your ears and mind and eyes" (390-391). Ironically, Tiresias turns Oedipus's accusations of blindness back on Oedipus by saying that it is really Oedipus who is truly blind, as we see in his lines:
You, even though you see clearly, do not see the scope of your evil, nor where you live, nor with whom you dwell. (433-435)
Hence, the recurring motif of sight and blindness is applied to both Tiresias and Oedipus to help portray the theme of limited perception and understanding.
The motif of light and darkness is frequently seen in relation to the gods and suffering, especially the current plague. The gods are portrayed as light or a saving, redeeming grace, while suffering is portrayed as darkness. The gods are asked to use their light and save the Thebans from their current state of darkness. Oedipus himself refers to the god Apollo and any messages the god delivers that will hopefully end the plague as light, as we see in Oedipus's lines, "Lord Apollo, if only he might come as bright with redeeming fortune as shine his eyes!" (86-87). Later, when the chorus delivers a long ode petitioning the gods for help, they also refer to the gods as saving light. They call on three gods, Zeus, Artemis and Phoebus for protection from their current troubles, as we see in their lines, "I call: my threefold protection from death, shine forth on me" (175). Hence we see that the recurring motif of light and darkness helps to portray protection and salvation as light, and death, destruction, and agony as darkness.