The Messiah would teach in parables.
OT Prophecy NT Fulfillment
Isaiah 6:9–10
[9] And he said, Go, and tell this people, Hear ye indeed, but understand not; and see ye indeed, but perceive not.
[10] Make the heart of this people fat, and make their ears heavy, and shut their eyes; lest they see with their eyes, and hear with their ears, and understand with their heart, and convert, and be healed.
Matthew 13:13–15
[13] Therefore speak I to them in parables: because they seeing see not; and hearing they hear not, neither do they understand.
[14] And in them is fulfilled the prophecy of Esaias, which saith, By hearing ye shall hear, and shall not understand; and seeing ye shall see, and shall not perceive:
[15] For this people's heart is waxed gross, and their ears are dull of hearing, and their eyes they have closed; lest at any time they should see with their eyes, and hear with their ears, and should understand with their heart, and should be converted, and I should heal them.
Tanakh – Neviim – Isaiah 6:9–10
[9] And He said: Go, and tell this people: hear ye indeed, but understand not; and see ye indeed, but perceive not.
[10] Make the heart of this people fat, and make their ears heavy, and shut their eyes; lest they, seeing with their eyes, and hearing with their ears, and understanding with their heart, return, and be healed.
Hebrew OT – Isaiah 6:9–10
[9] וַיֹּאמֶר לֵךְ וְאָמַרְתָּ לָעָם הַזֶּה
שִׁמְעוּ שָׁמוֹעַ וְאַל־תָּבִינוּ
וּרְאוּ רָאוֹ וְאַל־תֵּדָעוּ
[10] הַשְׁמֵן לֵב־הָעָם הַזֶּה
וְאָזְנָיו הַכְבֵּד
וְעֵינָיו הָשַׁע
פֶּן־יִרְאֶה בְעֵינָיו
וּבְאָזְנָיו יִשְׁמָע
וּלְבָבוֹ יָבִין
וָשָׁב וְרָפָא לוֹ