Lyric discussion by MasterOfLyrics 

I was thinking what HijoDelMetallica wrote. Clearly it's about the struggle to overcome an addiction (more generally, it could also refer to compulsive, destructive behavior).

There's nothing in this song to suggest anything regarding cancer, so I'm not quite sure where others are getting that from (other than some mysterious quote from James than no one seems to have a link to).

@MasterOfLyrics

Until it sleeps symbolises the cancer going into remission. It doesn't work if the song was was about depression. Other lyrics are "wash me, til I'm clean", again a reference to washing the cancer out until he's "clean".

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