Oedipus Rex reveals the prophecy which caused him to leave Corinth (791-93): "that I was fated to lie with my mother," "and show to daylight an accursed breed" "which men would not endure, and I was doomed" "to be murderer of the father that begot me." The implication of Laius's oracle is ambiguous. One interpretation considers that the presentation of Laius's oracle in this play differs from that found in Aeschylus's Oedipus trilogy produced in 467 BC. Helaine Smith argues: Sophocles had the option of making the oracle to Laius conditional ("if" Laius has a son, that son will kill him) or
Oedipus at Colonus of guilt; the fact that Oedipus is "rationally innocent" – that he sinned unknowingly – decreases his guilt, allowing his earthly sufferings to serve as sufficient expiation for his sins. Darice Birge has argued that "Oedipus at Colonus" can be interpreted as a heroic narrative of Oedipus rather than a tragic one. It can be viewed as a transitional piece from the Oedipus of "Oedipus Rex" whose acts were abominable to the Oedipus we see at the end of "Oedipus at Colonus", who is so powerful that he is sought after by two separate major cities. The major image used