'Leaven of the Pharisees' in the Bible

And Jesus said to them, “Watch out and beware of the leaven of the Pharisees and Sadducees.”

How is it that you do not understand that I did not speak to you concerning bread? But beware of the leaven of the Pharisees and Sadducees.”

And He was giving orders to them, saying, “Watch out! Beware of the leaven of the Pharisees and the leaven of Herod.”

Under these circumstances, after so many thousands of people had gathered together that they were stepping on one another, He began saying to His disciples first of all, “Beware of the leaven of the Pharisees, which is hypocrisy.