Divine Comedy: Paradiso Lesson Plan

As the poem progresses, Dante's vision is increasingly inadequate for the things he sees. Why is this the case?

The most obvious (and superficial) answer is that, as Dante ascends higher and higher, the things he sees become more and more resplendent, and therefore more and more difficult to comprehend. For those students who remember it, however, there is another, canonical answer given by Solomon, who tells Dante that souls' ability to bear the lights of Heaven depends on the strength of their love for God.

In what terms is Dante's journey through Heaven described? How has his way of describing the journey changed or remained the same throughout Paradiso?