Cause everybody knows keys open doors, but bricks open windows
The literal meaning has to do with the last line about robbing from cars, keys open the doors to the car but bricks can be used to “open” / break the windows, to steal the stuff inside the car.
On another level, a key is a kilo of coke, and a brick is a brick of coke. Drugs could open new doors and windows in your mind, like a new view.
Could also be a reference to the Clipse track “Keys Open Doors,” especially since Pusha T is on the record.
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