For three years, they had me peein' out of a cup
This is in reference to the urine-based drug test administered in prisons, due to Jay-Z’s 3 years Probation, for his stabbing case that involved Lance Un Rivera, as said in “Welcome to New York City” and “Dear Summer'
This could, however, be a reference to cups of sterile urine druggies will purchase so that they can pass narcotics tests. He’s “peeing out of a cup” in the sense that he’s pouring the purchased pee into the test cup instead of his own.
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