"I'm on fire, ay," that's what Richard Pryor say
from Kanye West (Ft. Ghostface Killah & Pusha T) – New God Flow Lyrics 2 on Rap Genius
Meaning
In 1980 Richard Pryor set himself on fire while trying to freebase (purify) some cocaine. While Kanye utters a similar expression, it has to do with music and not self-immolation.

http://www.youtube.com/watch?v=bjD4PHojNBU
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