Hebrews 5:11
I have much to say to you about this, but it is difficult to make it clear to you, because you have become so slow of apprehension.
2 Peter 3:16
speaking of it as he does in all his letters. There are some things in them hard to understand, which ignorant, unsteadfast people twist to their own ruin, just as they do the rest of the Scriptures.
Matthew 13:15
For this nation's mind has grown dull, And they hear faintly with their ears, And they have shut their eyes, So as never to see with their eyes, And hear with their ears, And understand with their minds, and turn back, And let me cure them!'
Mark 8:17-18
And he noticed it and said to them, "Why do you discuss your being without bread? Do you not yet see nor understand? Are your minds so dull?
Mark 8:21
He said to them, "Do you not understand yet?"
Luke 24:25
Then he said to them, "How foolish you are and how slow to believe all that the prophets have said!
John 6:6
Now he said this to test him, for he knew what he meant to do.
John 16:12
I have much more to tell you, but you cannot take it in now,
Acts 28:27
For this nation's mind has grown dull, And they hear faintly with their ears, And they have shut their eyes, So as never to see with their eyes, And hear with their ears, And understand with their minds, and turn back, And let me cure them!" '