Answer:
The incredible coincidence that surround the appearance of the messenger from Corinth and the shepherd was that he was both the messanger, and once he had been the shepard that found a baby on the woods near Thebes who he had helped, that baby happened to be Oedipus.
Explanation:
The messanger that was coming to tell Oedipus that his father Podipus was dead, was the same shepard that years ago found Oedipus abandoned. It was an incredible coincidence that he was giving a message to a man, that years ago he met as a baby.
