Matthew 13:13-14
Therefore I speak to them in parables; because seeing they see not, and hearing they hear not, neither do they understand.
Mark 4:12
in order that seeing they may see, and not know; and hearing they may hear, and not understand; lest they may turn, and their sins may he forgiven unto them.
Luke 8:10
And He said; To you it has been given to know the mysteries of the kingdom of God: but to the rest in parables; in order that seeing they may not see, and hearing they may not understand.
John 9:39-41
And Jesus said, For judgment I came into this world, that those not seeing may see; and those seeing may be made blind.
John 12:40
He hath blinded their eyes, and hardened their heart; in order that they may not see with their eyes, nor understand with their heart, and turn, and I shall heal them.
Mark 8:17-18
And Jesus knowing says to them, Why do you reason because you have not bread? do you not yet know, nor understand? have you your heart still hardened?
Acts 7:51-52
Ye stiffnecked and uncircumcised in heart and ears, you do always resist the Holy Ghost; as your fathers did, so do ye.
Acts 28:26-27
Go to this people, and say, By hearing ye shall hear, and may not understand; and seeing you shall see, and may not perceive:
Romans 11:7-8
What then? Israel did not attain that which he was seeking, but the election obtained it, and the rest were hardened:
2 Corinthians 3:14
But their minds were darkened. For until this day the same veil remains in the reading of the old covenant, remains, not lifted; because it is done away in Christ;
2 Corinthians 4:3-4
But if indeed our gospel is hidden, it is hidden with those who are lost:
Ephesians 4:18
being darkened in their understanding, alienated from the life of God through the ignorance being in themselves, on account of the blindness of their heart;
2 Thessalonians 2:10-11
and in all the deception of unrighteousness to those who perish; because they did not receive the divine love of the truth, that they might be saved.