Sophocles' Oedipus the King focuses much of its attention on oracles delivered by Apollo at Delphi. In at least two instances, Jocasta shows skepticism or even outright rejection of their validity.
In the scene in which Oedipus and Creon argue after Oedipus believes Creon has accused him of killing Laius, Jocasta recalls the oracle that Laius was destined to be killed by a child that he fathered with Jocasta. She claims that oracle never came to pass and she tells Oedipus not to "concern yourself with prophecies" (Ian Johnston translation). She reiterates this point later on because she believes that the child who was supposed to have killed Laius is now dead:
So as far as these oracular sayings go,
I would not look for confirmation anywhere.
Oedipus agrees, but still wants to summon the peasant who may be able to shed some light on the mystery.
After Oedipus and Jocasta exit, the members of the Chorus pray that the gods view all of their words and deeds as pious and reverent. They declare that "Insolence gives birth to tyranny" and they note that such insolence inevitably brings a person to ruin. They go on to observe that people who show no respect for the gods are eventually destroyed. They indicate that they are deeply troubled by the rejection of the validity of oracular responses:
Nowhere is Apollo honoured publicly,
and our religious faith is dying away.
Thus, the Theban elders are clearly disturbed by Jocasta's views on Apollo's oracular responses.