Aware of their discussion, Jesus asked them: "Why are you talking about having no bread? Do you still not see or understand? Are your hearts hardened?
Do you have eyes but fail to see, and ears but fail to hear? And don't you remember?
Mark Chapter 8: Verses 17 - 18
Whenever it seizes him, it throws him to the ground. He foams at the mouth, gnashes his teeth and becomes rigid. I asked your disciples to drive out the spirit, but they could not."
"O unbelieving generation," Jesus replied, "how long shall I stay with you? How long shall I put up with you? Bring the boy to me."
Mark Chapter 9: Verses 18 - 19
Later Jesus appeared to the Eleven as they were eating; he rebuked them for their lack of faith and their stubborn refusal to believe those who had seen him after he had risen.
Mark Chapter 16: Verse 14
He said to them, "How foolish you are, and how slow of heart to believe all that the prophets have spoken!
Did not the Christ have to suffer these things and then enter his glory?"
And beginning with Moses and all the Prophets, he explained to them what was said in all the Scriptures concerning himself.
Luke Chapter 24: Verses 25 - 27