Leaven (Yeast) of Other Evils
Source: Nav
1 Corinthians 5:6–8
Your boasting is not good. Do you not know that a little leaven works through the whole batch of dough? / Get rid of the old leaven, that you may be a new unleavened batch, as you really are. For Christ, our Passover lamb, has been sacrificed. / Therefore let us keep the feast, not with the old bread, leavened with malice and wickedness, but with the unleavened bread of sincerity and of truth.
Galatians 5:9
A little leaven works through the whole batch of dough.