What is anything which makes a general assimilating (especially a corrupting) change in the mass. Beware of the leaven of the Pharisees, which is hypocrisy. Luke xii called?

leaven — Anything which makes a general assimilating (especially a corrupting) change in the mass. Beware of the leaven of the Pharisees, which is hypocrisy. Luke xii. (Webster's 1913.)

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