Mark 6:52
for they understood not concerning the loaves, for their heart hath been hard.
Mark 3:5
And having looked round upon them with anger, being grieved for the hardness of their heart, he saith to the man, 'Stretch forth thy hand;' and he stretched forth, and his hand was restored whole as the other;
Mark 8:17-21
And Jesus having known, saith to them, 'Why do ye reason, because ye have no loaves? do ye not yet perceive, nor understand, yet have ye your heart hardened?
Isaiah 63:17
Why causest Thou us to wander, O Jehovah, from Thy ways? Thou hardenest our heart from Thy fear, Turn back for Thy servants' sake, The tribes of Thine inheritance.
Matthew 16:9-11
do ye not yet understand, nor remember the five loaves of the five thousand, and how many hand-baskets ye took up?
Mark 7:18
and he saith to them, 'So also ye are without understanding! Do ye not perceive that nothing from without entering into the man is able to defile him?
Mark 16:14
Afterwards, as they are reclining (at meat), he was manifested to the eleven, and did reproach their unbelief and stiffness of heart, because they believed not those having seen him being raised;
Luke 24:25
And he said unto them, 'O inconsiderate and slow in heart, to believe on all that the prophets spake!
Romans 11:7
What then? What Israel doth seek after, this it did not obtain, and the chosen did obtain, and the rest were hardened,