What gave the people in the city confidence in Oedipus so that they felt comfortable in accepting him as their king?

At the start of the play, the people of Thebes recognize that Oedipus has their best interests at heart, that he is as invested in ending the curse as they are. When the priest implores Oedipus to save the city: “Raise up our city, save it and raise it up” (51). Oedipus tells the collected crowd that even though he knows they are sick, none is as sick and devastated as he: thus clearly identifying himself with Thebes.