Hearing without understanding
Jesus said that Isaiah's words about people hearing without understanding were fulfilled among those who saw and heard but did not perceive.
And He replied: βGo and tell this people, βBe ever hearing, but never understanding; be ever seeing, but never perceiving.β Make the hearts of this people calloused; deafen their ears and close their eyes. Otherwise they might see with their eyes, hear with their ears, understand with their hearts, and turn and be healed.β
Isaiah 6:9-10 describes people who hear without understanding and see without perceiving; Matthew 13:14-15 quotes the passage after Jesus says that this is why He speaks to the crowds in parables.