Because there was a prophecy saying that their son would kill Laius and marry Jacosta.
A oracle predicted that thier son would kill Laius his father and marry Iocaste his mother.
Laius was the father of Oedipus who Oedipus killed.
Laius is Oedipus' real father in "Oedipus Rex" by Sophocles (495 B.C.E. - 405 B.C.E.).Specifically, Theban King Laius is the father of Theban King Oedipus. But Oedipus' parents leave him to die from exposure on the mountains outside Thebes because of a dreaded prophecy. Oedipus survives, is fostered into the Corinthian royal house, and has no idea that Laius is his biological father.
Jocasta hands the infant Oedipus over to the shepherd to be exposed in "Oedipus Rex" by Sophocles (495 B.C.E. - 405 B.C.E.).Specifically, Theban monarchs Laius and Jocasta receive a prophecy that their son will grow up to kill his father. Laius therefore makes it clear that Jocasta must kill her three-day-old infant son Oedipus. Jocasta does not want to disobey her husband, but also does not want to carry out the deed herself. She therefore asks her most trusted servant, a Theban shepherd, to leave Oedipus exposed to the ravaging weather and scrounging wildlife on the mountains outside Thebes.
Tiresias tells Oedipus he is the murderer of Laius.
Oedipus does not realize that he killed king Laius and that king Laius was his father.
Oedipus's real parents are Laius and Jocasta, the king and queen of Thebes. According to Greek mythology, Laius received a prophecy that his son would kill him, so he ordered the infant Oedipus to be abandoned. However, Oedipus was rescued and raised by the king and queen of Corinth, unaware of his true lineage.
Laius was father of Oedipus by Jocasta and the son of king Labdacus of Thebes.
Because the oracle told them that their son Ödipus would kill his father (i.e. Laius) and then marry his wife (Jocasta, Oedipus' mother)
At the time of Laius's murder, Oedipus was not king of Thebes; in fact he unknowingly killed Laius and was the son of Laius.
Oedipus did, but he didn't realize it was Laius. Also, no one knew it was Oedipus until towards the end.
Oedipus