Hebrews 5:11
Concerning whom we have much to say, and hard to be interpreted in speaking of it, since ye are become dull in hearing.
2 Peter 3:16
as also in all his epistles, speaking in them of these things; among which some things are hard to be understood, which the untaught and ill-established wrest, as also the other scriptures, to their own destruction.
Matthew 13:15
for the heart of this people has grown fat, and they have heard heavily with their ears, and they have closed their eyes as asleep, lest they should see with the eyes, and hear with the ears, and understand with the heart, and should be converted, and I should heal them.
Isaiah 6:10
Make the heart of this people fat, and make their ears heavy, and blind their eyes; lest they see with their eyes, and hear with their ears, and understand with their heart, and be converted, and healed.
Mark 8:17-18
And Jesus knowing it, says to them, Why reason ye because ye have no bread? Do ye not yet perceive nor understand? Have ye your heart yet hardened?
Mark 8:21
And he said to them, How do ye not yet understand?
Luke 24:25
And he said to them, O senseless and slow of heart to believe in all that the prophets have spoken!
John 6:6
But this he said trying him, for he knew what he was going to do.
John 16:12
I have yet many things to say to you, but ye cannot bear them now.
Acts 28:27
For the heart of this people has become fat, and they hear heavily with their ears, and they have closed their eyes; lest they should see with their eyes, and hear with their ears, and understand with their heart, and be converted, and I should heal them.
1 Kings 10:1
And the queen of Sheba heard of the fame of Solomon in connection with the name of Jehovah, and came to prove him with enigmas.