1 Corinthians 5:7-8
Cleanse out the old leaven that you may be a new lump, as you really are unleavened. For Christ, our Passover lamb, has been sacrificed.
Let us therefore celebrate the festival, h not with the old leaven, i the leaven of malice and evil, but with the unleavened bread of sincerity and truth.
English Standard Version (ESV) The Holy Bible, English Standard Version Copyright © 2001 by Crossway Bibles, a division of Good News Publishers.
Seven days you shall eat unleavened bread. On the first day you shall remove leaven out of your houses, for if anyone eats what is leavened, from the first day until the seventh day, that person shall be cut off from Israel.
You shall eat no leavened bread with it. Seven days you shall eat it with unleavened bread, the bread of affliction - for you came out of the land of Egypt in haste - that all the days of your life you may remember the day when you came out of the land of Egypt.
Jesus said to them, "Watch and beware of the leaven of the Pharisees and Sadducees.
Then they understood that he did not tell them to beware of the leaven of bread, but of the teaching of the Pharisees and Sadducees.
And he cautioned them, saying, "Watch out; beware of the leaven of the Pharisees and the leaven of Herod.
In the meantime, when so many thousands of the people had gathered together that they were trampling one another, he began to say to his disciples first, "Beware of the leaven of the Pharisees, which is hypocrisy.