After a long night of drinking, one way that the body gets rid of alcohol is through perspiration (sweat!) — but this also has a more figurative meaning dealing with a person being “corrupted” or “tainted”
In this song, Mack employs huge amounts of Christian (esp. Catholic) imagery. There are constant paralels between drinking and praying, as well as comparisons between rituals and aspects of Christian theology and those of an alcoholic.
In this particular case, the allusion is to Jesus Christ’s agony in the garden of Gethsemane:
“And being in anguish, he prayed more earnestly, and his sweat was like drops of blood falling to the ground.”
—Luke 22:44 (NKJV)
However, the alcoholic in anguish has drunk so much that he actually sweats vodka (a spirit). High amounts of alcohol in the bloodstream are used as evidence of excessive drinking. The very blood of the alcoholic is more liquor than blood. His or her very body has been altered by heavy alcohol abuse.
Altogether, an extremely powerful and nuanced metaphor that frther cements the similarities (and differences) between religion and addictive behaviour.
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