Isaiah 6:9
4 The sound of their voices shook the door frames, and the temple was filled with smoke. 5 I said, “Woe to me! I am destroyed, for my lips are contaminated by sin, and I live among people whose lips are contaminated by sin. My eyes have seen the king, the Lord of Heaven’s Armies.” 6 But then one of the seraphs flew toward me. In his hand was a hot coal he had taken from the altar with tongs. 7 He touched my mouth with it and said, “Look, this coal has touched your lips. Your evil is removed; your sin is forgiven.” 8 I heard the voice of the Lord say, “Whom will I send? Who will go on our behalf?” I answered, “Here I am, send me!” 9 He said, “Go and tell these people: “‘Listen continually, but don’t understand. Look continually, but don’t perceive.’ 10 Make the hearts of these people calloused; make their ears deaf and their eyes blind. Otherwise they might see with their eyes and hear with their ears, their hearts might understand and they might repent and be healed.”
Jonathan Isaiah 6:9
4 And the posts of the threshold of the temple moved at the voice of him that cried, and the house of the sanctuary was filled with cloudy darkness. 5 Then said I, Woe is me, for I have sinned, for I am a guilty man to reprove, and I dwell in the midst of a people polluted with sin: for mine eyes have seen the glory of the Shekinah of the King of the worlds, the Lord of hosts. 6 Then flew one of the ministers unto me, and in his mouth was a word, which he received from the Shekinah of Him who sat upon the throne of glory in the highest heavens, above the altar. 7 And he placed it in my mouth, and said, Behold, I have put the words of my prophecies in thy mouth, and thy iniquities are put away, and thy sins are expiated. 8 And I heard the voice of the Word of the Lord, which said, Whom shall I send to prophesy? and who will go to teach? Then said I, Here am I, send me. 9 And He said, Go, and tell this people, who are diligently hearing, but understand not, and see diligently, but know not. 10 Make the heart of this people fat, and make their ears heavy, and darken their eyes; lest they see with their eyes, and hear with their ears, and understand with their heart, and repent, and it shall be forgiven them.
Notes and References
"... Targumim may therefore enable us to find materials that are useful in comparison with the Gospels and the rest of the New Testament. In a scholarly age when comparison based on social models has become common, the Targumim provide insights into the treatment of Scripture among ordinary Jews. Another example illustrates an instance in which Jesus appears to have cited a form of Scripture that is closer to the Targum than to any other extant source. In such cases, an awareness that he does so helps us to understand his preaching better than the general similarity between Luke and Pseudo-Jonathan illustrates. Targum of Isaiah 6:9, 10 is an especially famous instance, and it helps to explain Mark 4:11, 12. The statement in Mark could be taken to mean that Jesus told parables with the express purpose “that” (Greek: hina) people might see and not perceive, hear and not understand, lest they turn and be forgiven ..."
Flesher, Paul V. M. & Chilton, Bruce The Targums: A Critical Introduction (pp. 387-388) Brill, 2011