Luke 12:1

Meanwhile as the people had gathered in tens of thousands, so that they were trampling upon one another, He began to say, first of all, to His disciples: "Beware of the yeast of the Pharisees, that is, hypocrisy.

James 3:17

The wisdom that is from above is first pure, then peaceable, gentle, willing to yield, full of compassion and good deeds, free from doubts and insincerity.

1 Corinthians 5:7-8

You must clean out the old yeast, that you may be a fresh lump, as you are to be free from the old yeast. For our Passover Lamb, Christ, has already been sacrificed.

Matthew 16:6-12

And Jesus said to them, "Look out, and keep on guarding yourselves against the yeast of the Pharisees and the Sadducees!"

Mark 8:15-21

Then He kept warning them by saying, "Look out! Keep on guarding yourselves against the yeast of the Pharisees and the yeast of Herod."

Luke 5:1

Once as the crowd was pressing against Him to hear the message of God, He found Himself standing on the shore of Lake Gennesaret.

Luke 5:15

But the news about Him continued to spread, and great crowds were gathering to hear Him and to be cured of their diseases.

Luke 6:17

Then He came down with them and took His stand on a level place, where there was a great throng of His disciples and a vast crowd of people from all over Judea and from Jerusalem and the seacoast district of Tyre and Sidon, who had come to hear Him and to be cured of their diseases.

Luke 11:44

A curse on you, because you are like unmarked graves which men walk over without knowing it!"

Luke 12:56

You hypocrites! You know how to interpret day by day the look of earth and sky. Then how is it that you do not know how to interpret the present crisis?

Acts 21:20

They gave the glory to God, when they heard it, and said to him, "You see, brother, how many thousand believers there are among the Jews, all of them zealous champions of the law.

1 Corinthians 15:3

For I passed on to you, among the primary principles of the good news, what I had received, that Christ died for our sins, in accordance with the Scriptures,

1 Peter 2:1

So once for all get rid of all malice, deceit, hypocrisy, envy, and all sorts of slander,

Treasury of Scripture Knowledge

Summary

In the mean time, when there were gathered together an innumerable multitude of people, insomuch that they trode one upon another, he began to say unto his disciples first of all, Beware ye of the leaven of the Pharisees, which is hypocrisy.

Bible References

First

1 Corinthians 15:3
For I passed on to you, among the primary principles of the good news, what I had received, that Christ died for our sins, in accordance with the Scriptures,
James 3:17
The wisdom that is from above is first pure, then peaceable, gentle, willing to yield, full of compassion and good deeds, free from doubts and insincerity.

Which

Luke 12:56
You hypocrites! You know how to interpret day by day the look of earth and sky. Then how is it that you do not know how to interpret the present crisis?
Luke 11:44
A curse on you, because you are like unmarked graves which men walk over without knowing it!"
James 3:17
The wisdom that is from above is first pure, then peaceable, gentle, willing to yield, full of compassion and good deeds, free from doubts and insincerity.
1 Peter 2:1
So once for all get rid of all malice, deceit, hypocrisy, envy, and all sorts of slander,

General references

Matthew 23:1
Then Jesus said to the crowds and to His disciples:
Luke 14:25
Now great crowds were going along with Him, and all at once He turned and said to them:
Galatians 5:9
A little yeast will transform the whole dough.