Overview
Leaven (yeast) served as a symbol of sin, corruption, and hypocrisy throughout Scripture. In the Old Testament, God commanded Israel to remove all leaven during Passover as a sign of separation from Egypt and commitment to holiness. In the New Testament, Paul uses leaven as a metaphor for how sin spreads through individuals and congregations, requiring decisive removal.
Key Scriptures
"Do you not know that a little leaven leavens the whole lump of dough?" (1 Corinthians 5:6, NASB). "Clean out the old leaven so that you may be a new lump, just as you are in fact unleavened. For Christ our Passover also has been sacrificed" (1 Corinthians 5:7, NASB). "For seven days no leaven shall be found in your houses; for whoever eats what is leavened, that person shall be cut off from the congregation of Israel" (Exodus 12:19, ESV).
Application
Examine your life and church community for patterns of sin or false teaching that, if left unchecked, will corrupt the whole body, and respond with the same seriousness Israel showed in removing leaven.