Oedipus as an infant is banished from his kingdom, his mother, Jocasta the Queen of Thebes having received a prophecy that he will grow up to marry his mother and kill his father, King Laius. As luck would have it he is adopted by king and queen of a neighboring country and raised as their own. When a similar prophesy is given to him he decides the most logical thing to do would be to get as far from his parents as possible in order to thwart fate. On the road he meets an argumentative man on a pilgrimage unwilling to give up the road. A scuffle takes place and in something akin to self defence, Oedipus kills the pilgrim and heads on toward the approaching kingdom. Upon his arrival the kingdom is up in arms and held hostage by a riddling witch. Oedipus solves the riddles and as a reward is given the kingdom, since King Laius has never returned. Oedipus then marries the widowed queen and everything seems as it should....and then he realizes he killed his father the pilgrim...and then he realizes he has married his mother and produced children that are his children/siblings....whereupon he gauges out his eyes and decides he must spend the rest of his life wandering through the wilderness with his daughter/sister.
Fate is a theme that often occurs in Greek writing, tragedies in particular, the concept of free will would have been foreign to a culture that espoused a religion of mercurial gods with ultimate power. The idea that attempting to avoid an oracle is the very thing which brings it about sets the stage for many Greek tragedies and becomes the foundation which many of the southern Gothic writers later explored. Oedipus the King is similar to Flannery O'Conner's "The Violent Bear It Away." Both Tarwater and Oedipus have been told their fate and both try to run away as far and as quick as possible and yet in the end both succumb to their destiny.