Mark 8:21
He said to them, "Do you not yet understand?"
Mark 6:52
for they had not understood about the loaves, because their hearts were hardened.
Matthew 16:11-12
How is it that you do not understand that I did not speak to you about bread? But beware of the leaven of the Pharisees and Sadducees."
Mark 8:12
And he sighed deeply in his spirit, and said, "Why does this generation seek a sign? Truly, I say to you, no sign shall be given to this generation."
Mark 8:17
Being aware of it, Jesus said to them, "Why do you discuss the fact that you have no bread? Do you not yet perceive or understand? Are your hearts hardened?
Mark 9:19
He answered him, "O faithless generation, how long shall I be with you? How long shall I bear with you? Bring him to me."
John 14:9
Jesus said to him, "Have I been with you so long, and yet you do not know me, Philip? He who has seen me has seen the Father; how can you say, 'Show us the Father'?
1 Corinthians 6:5
I say this to your shame. Can it be that there is no man among you wise enough to decide between his brethren,
1 Corinthians 15:34
Come back to your senses as you ought, and stop sinning; for some have no knowledge of God. I say this to your shame.