Christopher R. answered 05/09/24
Tutor for English and Ancient Greek
In the Ancient Greek imagination, fate and prophecy were entirely inescapable. Any effort to escape one's fate would inevitably lead them right into the very event or conclusion which they were trying so desperately to avoid. Oedipus is an excellent example of this both in the setting of the "bookends" of the story, as you mentioned in your original question, and also in the minutia of the plot. Oedipus, revolted by a prophecy that he should kill his father and marry his mother, leaves behind his supposed birthplace, Corinth, believing that he has just confounded fate by moving to Thebes, far enough away that he could never again come across his parents. Little does he know, of course, that the "parents" he left in Corinth were merely his adopted parents, and his birth parents are the king and queen of Thebes! By his very attempt to escape his fate, he allowed for its fulfillment.
We see this inescapability of fate in many other Greek writings, especially in Hesiod and Homer. In Works and Days, Hesiod describes how some days and dates are best for specific activities because of the inherent need for time to be ordered by fate and Zeus; for example, he writes:
Days come from Zeus. Keep good track of them,
And inform your workers that among civil folk
Who reckon things rightly, the Thirtieth is the day
For scheduling work and distributing supplies.
That reference to the Thirtieth day of the month is not a joke – Hesiod goes on to list the precise days of the month to shear sheep and bring in sheaves – which is the Eleventh and the Twelfth, by the way, though the Twelfth is always better than the Eleventh, for, “On that day the wispy spider spins her web". In Homer's Iliad, fate is shown to be something even beyond the will of Zeus, despite Zeus's attempts to convince his fellow Olympians of his omnipotence. A shining example of this comes at the end of the epic, when the time for Hector's death at the hands of Achilles is finally fulfilled. Zeus, with a heavy heart, "weighs the fates" of Hector and Achilles, and without any interference from Zeus, Hector's side of the scale "tips toward Hades". Ostensibly, the day which had forever been appointed for Hector's death had come, and even Zeus could not stop it. Hera reminds him of as much in Book 16, when she reproaches him for even suggesting that he could act contrary to fate.
And if nothing else, the names of the three personifications of Fate will tell you something about the Greeks' understanding and imagination. Their names are Klotho, Lakhesis, and Atropos. It's the last one you have to watch out for; she's the one who cuts off the thread of your life, after the other two have spun it out and woven it together, and her name means "the one who cannot be turned". No matter how you try to forestall your own death, the death of a loved one, or any other tragedy prophesied to befall you, it cannot be turned.