The glazed look is what every teacher dreads. That point when the teacher realises that his material has completely outstripped the comprehension of the student.
The writer to the Hebrews was afraid of the glazed look as he reached the end of chapter 5.
In the first few chapters he has warmed to his theme: Jesus is the son of God, greater than Moses, a High Priest greater than those descended from Aaron. Then as he feels comprehension slipping he says: 'We have much to say about this but it is hard to explain because you are slow to learn.'
