The figure of Gower is an interesting one; if other characters in the play seem to return from the dead, Gower really is reborn. He is the onstage presence of a fourteenth century author who wrote the most important source for Pericles. In his Confessio Amantis, John Gower told the tale of Apollonius of Tyre, who led a life of similar incident to Pericles's. The shift in the name from Apollonius to Pericles may come from other sources, such as Sir Philip Sidney's Arcadia or Plutarch's Lives or other classical sources.
Gower functions in the play as a kind of chorus, commenting on the action that has passed and initiating dumb shows, in which actions are pantomimed to move along the plot of the play. Gower is designed to give a medieval feel to the play. Initially he speaks in rhymed tetrameter couplets, and echoes the language of the medieval poet Gower himself. His eight monologues, filled with moralizing speeches, recount much of the action of the play.
Antiochus's challenge for the hand of his daughter echoes other scenes in Shakespeare and classical literature. A father's insistence that all suitors solve a riddle before marrying a daughter is central to Merchant of Venice, where Bassanio answers the riddle and marries Portia. However, for Bassanio, punishment for getting the riddle wrong was celibacy rather than death, and Portia's father was already dead. The riddle scene, coupled with the theme of incest, also evokes Sophocles's Oedipus Rex, when Oedipus solves the riddle of the Sphinx and proceeds onto his fate of killing his father and sleeping with his mother.
While Pericles discovers the truth of the riddle, he decides not to reveal it, claiming that something so awful ought to be kept secret. Antiochus understands that Pericles knows the truth but doesn't admit it. Pericles is doomed to death for not answering the riddle--yet Antiochus gives him forty days before his sentence, clearly leaving a window for escape for Pericles. Why doesn't the king kill Pericles then and there? Of course, the simple answer is that then there would be no play--the impetus for the action is Pericles's need to flee Antiochus and his assassins, and similarly to flee the idea of incest. Antiochus, for his part, may have offered the forty-day reprieve to Pericles as a gesture of thanks to Pericles for not spouting the truth of the riddle in front of his court. Or he may have opened a possibility for Pericles's flight out of an unconscious desire to have his secret known, while he still sends a murderer after Pericles to make sure the secret is contained. With Oedipus Rex and the taboo of incest at the heart of Sigmund Freud's exploration of the nature of unconscious desires, unconscious desires in Antiochus, another incestuous king, can't be ignored.
Antiochus is the first of many kings we meet in the play. Look for doubling of the relationship between Antiochus and his daughter and the relations between other kings and daughters elsewhere in the play.