They think that I'm a new jack but only if they knew that
They who think wrong are they who can't do that

from Rakim – I Ain't No Joke Lyrics on Rap Genius

Meaning

Rakim’s critics seem to think Rakim is young and inexperienced, a new jack, when he actually is the real deal.

To help improve the meaning of these lyrics, visit “I Ain't No Joke” by Rakim Lyrics and leave a comment on the lyrics box