Mark 6:52
For they understood not the loaves; for their heart was hardened.
Mark 3:5
And having looked round upon them with anger, grieved for the hardness of their heart, he says to the man, Stretch out thy hand. And he stretched out: and his hand was restored whole as the other.
Mark 8:17-21
And Jesus having known, says to them, Why reason ye with yourselves, because ye have no loaves? observe ye not yet, neither understand? have ye your heart yet hardened?
Isaiah 63:17
Wherefore, O Jehovah, wilt thou cause us to wander from thy ways, wilt thou harden our heart from thy fear? turn back for sake of thy servants, the tribes of thine inheritance.
Matthew 16:9-11
Do ye not yet understand, nor remember the five loaves of five thousand, and how many baskets ye took?
Mark 7:18
And he says, So are ye also without understanding? Do ye not perceive, that anything from without entering into a man, cannot pollute him
Mark 16:14
Afterwards to those reclining at table was he manifested, and he reproached their unbelief and hard heart, because they believed not them having seen him raised.
Luke 24:25
And he said to them, O ye unwise, and slow in heart to believe in all things which the prophets spake:
Romans 11:7
What then What Israel seeks for, this be attained not; but the selection attained, and the rest were hardened.