Marcos 8:15

Jesus evidently used the leaven in the loaf of bread as an object lesson to illustrate the pervasive corrupting teaching of the Pharisees and of Herod. Leaven was a common metaphor for corruption in both Jewish and Hellenistic circles. [Note: Lane, p. 280.] The teaching of the Pharisees was that Jesus received His authority from Satan rather than from God (Mark 3:22; cf. Mark 7:8-13). It was a denial of His role as God’s anointed Servant, Messiah. The teaching of Herod Antipas, what he believed and articulated, was likewise that Jesus was not the Messiah. Herod told others that Jesus was just John the Baptist come back to life (Mark 6:14-16). The Pharisees and Herod, though so different from each other in many respects, promoted the same heretical view that Jesus was not the Messiah, much less divine. In short, this leaven was unbelief. Another view is that the yeast of the Pharisees was their hypocritical, self-righteous traditionalism and the yeast of Herod was his spirit of imperial pride. [Note: Bailey, p. 80.]