Six blade knife is a metaphor for a six pack of beer and describes Mark's struggle with alcohol in his younger days. Alcohol gives you everything in the beginning and then takes it all away. "Take away the top of the tin" is a literal reference to removing the tab on a can of beer. However, Mark let's you know that the six blade knife doesn't have to be alcohol, "it can be just what you want it to be". A needle (heroin), a wife (toxic relationship). Something, like alcohol, that "you just can't see" taking hold of your mind before its too late.
The chorus is literally him saying he wants to stop drinking, to be free of the clutches of alcohol.
Six blade knife is a metaphor for a six pack of beer and describes Mark's struggle with alcohol in his younger days. Alcohol gives you everything in the beginning and then takes it all away. "Take away the top of the tin" is a literal reference to removing the tab on a can of beer. However, Mark let's you know that the six blade knife doesn't have to be alcohol, "it can be just what you want it to be". A needle (heroin), a wife (toxic relationship). Something, like alcohol, that "you just can't see" taking hold of your mind before its too late.
The chorus is literally him saying he wants to stop drinking, to be free of the clutches of alcohol.