Mark 8:17-18
And as He noticed it He said to them, "Why are you discussing the fact that you have no bread? Do you not yet know nor understand? Are your minds so dull?
Luke 24:25
Then He said to them, "O men sluggish in mind and slow in heart to believe all that the prophets have said!
John 3:19
And the ground for the sentence is this, that the light has come into the world, and yet, because their actions were evil, men have loved darkness more than the light.
Matthew 13:14
So in them the prophecy of the prophet Isaiah is fulfilled, which says: "'You will listen and listen and not understand, and you will look and look and never see at all,