It is widely acknowledged that William Blake''s longer works are very complex and not often well understood. Moreover, some of the best criticism on Blake''s prophetic books has a tendency to be nearly as complex and difficult to understand as the work it studies. But Blake''s work is difficult for a very specific reason, a reason put forward by Blake himself on several occasions. Specifically, Blake''s understanding of the sublime and its uses in art is the cause for much of what we find or term "difficult" in Blake''s work. Understanding the role and the goal of the sublime as it functions in Blake''s work is not only to better understand the context of his ideas in the discourses on the sublime occurring throughout his lifetime, but also to better understand the achievements of his books, and thereby hopefully gain a new appreciation of Blake as artist, thinker, and philosopher even in the midst of his most challenging techniques. Anyone with an interest in the spiritual, the sublime, the uses and pleasures of poetry should benefit from this close reading of one of the most masterful poems in the English language.