A classic song from Dylan’s John Wesley Harding. The meaning is cryptic; there have been theories of it being about everything from the Vietnam War to Armageddon. Some critics have noted parallels with Isaiah 21:5-9:

5: Prepare the table, watch in the watchtower, eat, drink: arise, ye princes, and anoint the shield.
6: For thus hath the Lord said unto me, Go, set a watchman, let him declare what he seeth.
7: And he saw a chariot with a couple of horsemen, a chariot of asses, and a chariot of camels; and he hearkened diligently with much heed:
8: And he cried, A lion: My lord, I stand continually upon the watchtower in the daytime, and I am set in my ward whole nights:
9: And, behold, here cometh a chariot of men, with a couple of horsemen. And he answered and said, Babylon is fallen, is fallen; and all the graven images of her gods he hath broken unto the ground.

Only Mr. Dylan will ever really know.

Jimi Hendrix covered this song, and it led to one of the greatest cover versions of all time. Even Dylan said he was a huge fan.