What is the code of blood vengeance in Oedipus?

In "Oedipus Rex," the code of blood vengeance refers to the moral and social obligation to avenge a familial wrongdoing, often leading to a cycle of violence and retribution. This code is exemplified by Oedipus's pursuit of the truth regarding King Laius's murder, which ultimately reveals his own guilt and tragic fate. The theme highlights the destructive nature of vengeance and the inescapable consequences of one's actions within the familial and societal context. Ultimately, it illustrates the tension between fate and free will in human lives.