1) The poem depicts a world that is falling into disorder and chaos. Images of a falcon flying away from its handler and a "blood-dimmed tide" drowning innocence are used to represent this breakdown of traditional structures.
2) The narrator has a vision of a mysterious beast, with the body of a lion and head of a man, that seems to herald some kind of ominous change rather than the Christian vision of the Second Coming.
3) The poem presents a darker and more pessimistic view of the future as the speaker questions what kind of "rough beast" is heading to Bethlehem to be born, suggesting the end of the old world order and the birth of some unknown threat