5 And I said: “O wretched that I am! I am stunned; for being a man and having unclean lips, I live among a people having unclean lips, and I have seen the King, the Lord Sabaoth, with my eyes!” 6 Then one of the seraphin was sent to me, and he had in his hand a live coal that he had taken from the altar with the tongs. 7 And he touched my mouth and said: “Behold, this has touched your lips, and it will take away your lawlessness and purify your sins.” 8 Then I heard the voice of the Lord saying, “Whom should I send, and who will go to this people?” And I said, “Here am I; send me!” 9 And he said, “Go, and say to this people: ‘You will listen by listening, but you will not understand, and looking you will look, but you will not perceive.’ 10 For this people’s heart has grown fat, and with their ears they have heard heavily, and they have shut their eyes so that they might not see with their eyes and hear with their ears and understand with their heart and turn—and I would heal them.” 11 Then I said, “How long, O Lord?” And he said: “Until cities become desolate, because they are not inhabited, and houses, because there are no people, and the land will be left desolate.

37 Although Jesus had performed so many miraculous signs before them, they still refused to believe in him, 38 so that the word of the prophet Isaiah would be fulfilled. He said, “Lord, who has believed our message, and to whom has the arm of the Lord been revealed?” 39 For this reason they could not believe because again Isaiah said, 40 “He has blinded their eyes and hardened their heart, so that they would not see with their eyes and understand with their heart, and turn to me, and I would heal them.” 41 Isaiah said these things because he saw Christ’s glory and spoke about him.