Matthew 16:12

12 Then they understood that he was not telling them to guard against the yeast used in bread, but against the teaching of the Pharisees and Sadducees.

Read Matthew 16:12 Using Other Translations

Then understood they how that he bade them not beware of the leaven of bread, but of the doctrine of the Pharisees and of the 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.
Then at last they understood that he wasn’t speaking about the yeast in bread, but about the deceptive teaching of the Pharisees and Sadducees.

What does Matthew 16:12 mean?

John Gill's Exposition of the Bible
Matthew 16:12

Then understood they
Without any further explication of his sense and meaning,

how that he bade them not beware of the leaven of bread:
which sense they first took him in; imagining, because the Pharisees were very particular and precise what sort of leaven they made use of F26, that Christ forbad them buying bread that was made with leaven according to their directions: and since their rules in everything prevailed much in all places, they were concerned what bread they must, or could buy; but now they perceived that he did not speak of this, but of the doctrine of the Pharisees and of the Sadducees. It was very common with the Jews F1 to call the corruption and vitiosity of nature by the name of (hoyebv rwav) , "leaven in the lump": hence our Lord calls their doctrine so, because it proceeded from thence, and was agreeable thereunto; and uses the phrase on purpose to expose it, and bring it into neglect and contempt.


FOOTNOTES:

F26 Misn. Pesach, c. 2. sect. 2, 3. T. Hieros. Sabbat, fol. 3. 3.
F1 T. Hieros. Beracot, fol. 7. 4. T. Bab. Beracot, fol. 17. 1. Bereshit Rabba, fol. 29. 4. Caphtor, fol. 38. 2. Tzeror Hammor, fol. 73. 2.
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