Matthew 13:14-15

So they show that the things Isaiah said about them are true: ‘You will listen and listen, but you will not understand. You will look and look, but you will not learn. For the minds of these people have become stubborn. They do not hear with their ears, and they have closed their eyes. Otherwise they might really understand what they see with their eyes and hear with their ears. They might really understand in their minds and come back to me and be healed.’