They did it again. The lyrics to this song are artfully composed and take a wonderful detour into imagery and metaphors. In my limited opinion and interpretation, the song is about an individual who lived the fast lane on a set of values--of which substance was lacking. At one point in time, these goals and mores suited his lifestyle, but he now finds that world he once "ruled" empty and void of anything that truly fulfills him. His request for a "mirror, sword and shield" seem to be a cry for help--to keep him always aware of who he is (mirror), but to be his strength and solace (sword and shield, respectively). He is, arguably, referring to his soul, conscience, his sense of self, or all three. "People could not believe what I'd become" suggests that he started out at the top of his game, but then eventually took it too far. He's a fallen god so to speak (Which seemingly ties in the historical references in the refrain.) It is truly a beautiful song, and follows Coldplay's trend in writing songs that find a common thread of pain/love/joy/disappointments, etc., and then to create a sanctuary by letting us all know that we have all experienced that in our lives.