Acts 28:26
Saying, Go unto this people, and say, Hearing ye shall hear, and shall not understand; and seeing ye shall see, and not perceive: Saying, Go unto this people, and say, Hearing ye shall hear, and shall not understand; and seeing ye shall see, and not perceive:
The verse belongs to the account of the journey to Rome with the centurion and his prisoners, sailing from Melita to Puteoli on the Alexandrian ship Castor and Pollux after the opening of navigation. It was spoken by the Holy Spirit through Isaiah to the fathers and was repeated later to describe the present situation. It means that this people hear without understanding and see without perceiving because their heart has grown dull, their ears are dull of hearing, and they have closed their eyes, lest they see with their eyes and hear with their ears and understand with their heart and be converted and be healed. People may hear God's truth and see its evidence yet fail to understand because their hearts have grown dull and they have closed their eyes and ears.
It was applied to the Jews who rejected the truth about Jesus, whose refusal kept them from understanding, turning to God, and receiving healing. This failure to understand comes from deliberate resistance, for though convinced in their understanding by seeing the works done, proud and stubborn hearts in self-righteousness refused to acknowledge the Messiah. They resisted evidence and demanded further signs that would not have changed their unbelief. Because of this rejection, the salvation of God is sent to the Gentiles, who will hear it.