You could get a smack for this
I ain't no joke

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

Meaning

EPMD later sampled their “smack you back” line in “Get the Bozack”

http://youtu.be/PRh_Njm4pS0?t=14s

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