What does Oedipus realize when Queen Jocasta, his wife, tells him where King Laius was killed?

In the
story of the King,
Queenand Oedipus discuss the prospect of Oedipus being
the murderer of King
Laius.  This discussion happens directly afterattempts to persuade Oedipus

that he is the killer of Laius, and Oedipus in turn blamesfor the murder due to this
accusation.
 Jocasta enters the scene to interject herself between her
quarreling husband and brother and
begins to question Oedipus about what has
upset him.  Oedipus...