Another parable He spoke to them: "The kingdom of heaven is like leaven, which a woman took and hid in three measures of meal till it was all leavened."
— Matthew 13:33
Jesus said the kingdom of heaven is like leaven, a comparison that may not mean a lot to us today. But it would have been immediately understood by the people of His day. Leaven is like yeast, and it always has negative connotations in Scripture.
Before the Passover, Moses instructed the Israelites, "Seven days you shall eat unleavened bread. On the first day you shall remove leaven from your houses . . . " (Exodus 12:15). Picking up on this theme, Paul wrote to believers in Corinth who were actually boasting about welcoming a compromising believer: "Your glorying is not good. Do you not know that a little leaven leavens the whole lump? Therefore purge out the old leaven, that you may be a new lump, since you truly are unleavened. For indeed Christ, our Passover, was sacrificed for us" (1 Corinthians 5:6–7). Jesus also said, "Take heed and beware of the leaven of the Pharisees and the Sadducees" (Matthew16:6).
Before the Passover, Moses instructed the Israelites, "Seven days you shall eat unleavened bread. On the first day you shall remove leaven from your houses . . . " (Exodus 12:15). Picking up on this theme, Paul wrote to believers in Corinth who were actually boasting about welcoming a compromising believer: "Your glorying is not good. Do you not know that a little leaven leavens the whole lump? Therefore purge out the old leaven, that you may be a new lump, since you truly are unleavened. For indeed Christ, our Passover, was sacrificed for us" (1 Corinthians 5:6–7). Jesus also said, "Take heed and beware of the leaven of the Pharisees and the Sadducees" (Matthew16:6).