Teiresias 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, Teiresias became a priestess of Hera, married and had children, including Manto. Tiresias's background was important, both for his prophecy and his experiences. Greek mythology contained other hermaphroditic figures (including Hermaphroditus), but Tiresias was fully male and then fully female. Also, prophecy was a gift given only to the priests and priestesses. Therefore, Teiresias offered Zeus and Hera evidence and gained the gift of male and female priestly prophecy.
As a seer, Teiresias was regarded as inerrant. In Greek literature, Teiresias's pronouncements are always gnomic but never wrong. He is generally extremely reluctant to offer his visions like most Oracles. Often when his name is attached to a mythic prophecy, it is introduced simply to supply a personality to the generic example of a seer. In Sophocles' Oedipus the King, Oedipus, the king of Thebes, calls upon Teiresias to aid in the investigation of the killing of the previous king Laios. At first, Teiresias refuses to give a direct answer and instead hints that the killer is someone Oedipus really does not wish to find. However, after being provoked to anger by Oedipus' accusation first that he has no foresight and then that Teiresias had had a hand in the murder, he reveals that in fact it was Oedipus himself who had committed the crime. Outraged, Oedipus throws him out of the palace, but then afterwards realises the truth. Thus, Teiresias was seen as a powerful seer because the downfall of the mighty Oedipus was seen by Teiresias.
