Mark 6:52
For they considered not the miracle of the loaves; for their heart was hardened.
Mark 3:5
And when he had looked around on them with anger, being grieved for the hardness of their hearts, he saith to the man, Stretch forth thy hand. And he stretched it out: and his hand was restored whole as the other.
Mark 8:17-21
And when Jesus knew it, he saith to them, Why reason ye, because ye have no bread? perceive ye not yet, neither understand? have ye your heart yet hardened?
Isaiah 63:17
O LORD, why hast thou made us to err from thy ways, and hardened our heart from thy fear? Return for thy servants' sake, the tribes of thy inheritance.
Matthew 16:9-11
Do ye not yet understand, neither remember the five loaves of the five thousand, and how many baskets ye took up?
Mark 7:18
And he saith to them, Are ye so void of understanding also? Do ye not perceive, that whatever thing from without entereth into the man, it cannot defile him.
Mark 16:14
Afterward he appeared to the eleven, as they sat at table, and upbraided them with their unbelief, and hardness of heart, because they believed not them who had seen him after he was risen.
Luke 24:25
Then he said to them, O fools, and slow of heart to believe all that the prophets have spoken!
Romans 11:7
What then? Israel hath not obtained that which he seeketh for; but the election hath obtained it, and the rest were blinded.