Oedipus Rex : Why was Tiresias cursed?

First, who is Tiresias in the play? In Greek mythology, Tiresias was a blind prophet, the son of the shepherd Everes and Chariclo. A variant spelling of his name is Teiresias. During Dr. Edwin's class a couple of weeks ago, he did ask us to find the reasons on why Tiresias was cursed by the Gods. After I did some research on the Internet, here are the reasons ~

Tiresias was a priest of Zeus, and as a young man he encountered two snakes mating and hit them with a stick. He was then transformed into a woman. As a woman, Tiresias became a priestess of Hera, married and had children, including Manto. According to some versions of the tale, Lady Tiresias was a prostitute of great renown. After seven years as a woman, Tiresias again found mating snakes, struck them with her staff, and became a man once more. As a result of his experiences, Zeus and Hera asked him to settle the question of which sex, male or female, experienced more pleasure during intercourse. Zeus claimed it was women; Hera claimed it was men. When Tiresias sided with Zeus, Hera struck him blind. Since Zeus could not undo what she had done, he gave him the gift of prophecy.

Tiresias's background was important, both for his prophecy and his experiences. Greek mythology contained other hermaphroditic (a person, animal or flower that has both male and female reproductive organs) figures such as Hermaphroditus (the child of Aphrodite and Hermes) but Tiresias was fully male and then fully female. Also, prophecy was a gift given only to the priests and priestesses. Therefore, Tiresias offered Zeus and Hera evidence and gained the gift of male and female priestly prophecy. An alternative and less commonly told story has it that Tiresias was blinded by the goddess Athena after he stumbled onto her bathing naked. His mother, Chariclo, begged her to undo her curse, but Athena couldn't; she gave him prophecy instead. =)