The Sign of Jonah and the Leaven of the Leaders
Pharisees and Sadducees seek a sign, but Jesus again points to Jonah and warns disciples against the leaders’ “leaven.” The disciples initially think about literal bread until Jesus reminds them of both miraculous feedings; lack of bread cannot be the problem.
Where this fits in the story: Jonah has already become Jesus’ sign of death-and-restoration, while leaven here functions as spreading teaching/influence rather than a universal symbol for sin.
Where Scripture takes it next: Peter soon confesses Jesus’ identity correctly, yet immediately misunderstands what Messiahship requires.