This hamartia (tragic flaw, the same word that early Christians will use for "sin," especially for original sin, the sin we are born with, the sin beyond any human being's control) is not incidental to Oedipus but is, rather, essential to his admirable character. He is strong, courageous, self-possessed, taking charge and striding boldly where others fear to go—the very qualities that foretell his undoing.
Ch.IV The Politician and the Playwright: How to Rule - Sailing the Wine-Dark Sea: Why the Greeks Matter (2003)