Oedipus's tragedy because of believes prophecy or not?

Is oracle real? Is the reason of Oedipus's tragedy coming true because he believes prophecy or disbelieves it? There are pivotal 3 oracles. The first is when Oedipus was birth. Oedipus’s genuine parents trust the prophecy that he would kill his father and marry his mother. Then the Apollo oracle told him that he would murder his father and marry his mother when he grew up raised by adopter who are King and Queen of Isthmus. The third oracle comes out involving that there is plague in Thebe. As the King of Thebe, Oedipus sends Creon to Apollo’s home at Pytho. Apollo says which Thebe will be healed only until the killer of Laius King found.

The whole play are connected by these three oracles. With developing of these oracles, Oedipus are closer and closer to his destiny.  

Is that an irony? On the one hand, when he trusts what Apollo says, he is leaded to direction of the answer. “Phoebus clearly ordered us, my lord, to drive out the pollution being fostered in this very land, not to nurture it unhealed.” (Sophocles lines 102-04). He believes it, and promises to find out who is the killer. This belief becomes the beginning of his unknown secrete exposed. On another hand, he tries to prove that he is a perfect King and defenses his fate from prophecies. Oedipus says, “But I deem myself the child of Chance, who gives good things, and I will not be dishonored. She is my mother, and brothers, the Months, have seen me both small and great. Being born what I am, I could never be another so I should seek out my descent.” (Sophocles lines 1102-07). He ignores Jocasta’s advise but goes forward of it. However, things are getting deeper and clearer. He is like betting his destiny for against the prophecy.

Whatever Oedipus believes the prophecy or not, he is destined to be made fun by his fate. Even though he struggles and wants to confirm he isn’t that unlucky in the end, it only brings him to downfall more quickly. In the end, Oedipus kindly has noticed his prophecy has come true, but he denies as a blind.