Listen not to what he speaks, that's been the cursing of his cause
Lupe has been using the demon metaphor for the last four bars. He’s saying this character is possessed, so he is yelling out the blasphemy and curses, similar to the little girl in the exorcist
However, this is just non-coherent profanities, so you shouldn’t listen to what is being said or take it to heart.
What he means is when we are consumed by the evils of the world, the things that we say are evil, too. Those who have yet to be consumed shouldn’t listen to those who are, because their words are skewed by that evil.
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