It would be incredibly difficult after only one read to actually give an accurate description of what happens in "The Book of Urizen." From what I can tell, Urizen was an immortal who wrote a book that established the seven deadly sins and many other religious elements. He was then trapped in a dark pit for several "ages" where he experienced nothing but woe. The rest of the poem mirrors much of the book of Genesis in the Bible. There is a creation story but it is seen from the perspectives of the immortals. Urizen helps with the creation of man but is later horrified to discover that the beings he created are completely miserable. Near the end of the poem, Blake makes clear what his primary message is. After the description of the pain Urizen sees Blake writes, "And all call'd it, The Net of Religion" (Ch. 25, Line 22). The poem ends with man establishing the foundations of Christianity and Urizen's descendants leaving the land of Egypt.
Blake's style is characterized by biblical prophecy and vivid imagery. Descriptions of blood, rage, misery, and a dark cavernous abyss permeate the text. Overall, this poem is dark, epic, and powerful. Additional research will be necessary to get a better impression of exactly who or what Urizen, Los, Enitharmon, and others are supposed to represent. After giving more time and focus to this poem I will undoubtedly come to different or more thought out conclusions as to what exactly is going on.
Note to students: Remember that we are not expecting you to fully understand anything we have you read after only one sitting. There is nothing wrong with misinterpreting or misunderstanding aspects of a poem after a quick first read. The goal is for you to do additional reading and research in order to form a fuller opinion. This blog provides an opportunity to get your first impressions out there and begin to at least gain a basic understanding of the text.