John 8:27

They did not realize that He had been speaking to them about the Father.

Isaiah 6:9

He said, “Go, and tell this people:
‘Keep on listening, but do not perceive;
Keep on looking, but do not understand.’

Isaiah 42:18-20

Hear, you deaf!
And look, you blind, that you may see.

Isaiah 59:10

We grope along the wall like blind men,
We grope like those who have no eyes;
We stumble at midday as in the twilight,
Among those who are vigorous we are like dead men.

John 8:43

Why do you not understand what I am saying? It is because you cannot hear My word.

John 8:47

He who is of God hears the words of God; for this reason you do not hear them, because you are not of God.”

Romans 11:7-10

What then? What Israel is seeking, it has not obtained, but those who were chosen obtained it, and the rest were hardened;

2 Corinthians 4:3-4

And even if our gospel is veiled, it is veiled to those who are perishing,

Treasury of Scripture Knowledge

Summary

They understood not that he spake to them of the Father.

Bible References

General references

John 8:43
Why do you not understand what I am saying? It is because you cannot hear My word.
Isaiah 6:9
He said, “Go, and tell this people:
‘Keep on listening, but do not perceive;
Keep on looking, but do not understand.’
Isaiah 42:18
Hear, you deaf!
And look, you blind, that you may see.
Isaiah 59:10
We grope along the wall like blind men,
We grope like those who have no eyes;
We stumble at midday as in the twilight,
Among those who are vigorous we are like dead men.
Romans 11:7
What then? What Israel is seeking, it has not obtained, but those who were chosen obtained it, and the rest were hardened;
2 Corinthians 4:3
And even if our gospel is veiled, it is veiled to those who are perishing,