Answer: He eagerly answers.
Explanation:
The servant eagerly answers the Oedipus. He will point out to him the fact that Oedipus is a baby abandoned by his parents. At that moment, the old man shows signs of fear, begs the messenger to stop and "keep his mouth shut." Oedipus, the messenger, learns that Polybus, King of Corinth, Oedipus's father, has died of old age.
I know this may not be what you are looking for. But this may help- the definition of irony is basically the expression of ones meaning by using language that usually signifies the opposite, typically for a humorous of opposite effect. So basically making a joke that is the opposite from what you think.
Unlike I think hope it helps