and not perceive
Isaiah 6:9 (KJV) 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.
11 Then said I, Lord, how long? And he answered, Until the cities be wasted without inhabitant, and the houses without man, and the land be utterly desolate,
12 And the Lord have removed men far away, and there be a great forsaking in the midst of the land.
Acts 28:23 (KJV) And when they had appointed him a day, there came many to him into his lodging; to whom he expounded and testified the kingdom of God, persuading them concerning Jesus, both out of the law of Moses, and out of the prophets, from morning till evening.
24 And some believed the things which were spoken, and some believed not.
25 And when they agreed not among themselves, they departed, after that Paul had spoken one word, Well spake the Holy Ghost by Esaias the prophet unto our fathers,
26 Saying, Go unto this people, and say, Hearing ye shall hear, and shall not understand; and seeing ye shall see, and not perceive:
27 For the heart of this people is waxed gross, and their ears are dull of hearing, and their eyes have they closed; lest they should see with their eyes, and hear with their ears, and understand with their heart, and should be converted, and I should heal them.
28 Be it known therefore unto you, that the salvation of God is sent unto the Gentiles, and that they will hear it.
29 And when he had said these words, the Jews departed, and had great reasoning among themselves.