Lyric discussion by Chris_Geez 

I've always thought it was about alcohol itself, and the effect James maybe felt it had on him and others. So, essentially James is writing the song as if Alcohol was a person/entity itself, and James takes on the perspective of Alcohol.

"Pure Black looking clear" - Alcohol is often clear, but can have a "dark" effect.

"You'll Suffer unto Me" - Alcohol has now become your master. Much like Drugs in "Master of Puppets".

"Let the Beatings Begin" - Not necessarily beating someone else up, but pschologically beating yourself up because you've fallen off the wagon, or you hate how you are after drinking and therefore beat yourself up over it.

"Your Loss Becomes My Gain" - Often Alcoholics will continue to drink because it numbs whatever their pain they're going through.

"Harvester of Sorrow Language of the Mad" - This is saying that alcohol will only make you depressed, and that it'll make you mad, as often alcoholic end up.

Interestingly, when you view this in context of the time, James was reportedly going through his partying/drinking phase, which would culiminate in his checking into rehab many years later, during "St. Anger".

So, as quite often the case, maybe this song was a form of subconscious therapy for James at the time.

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