Chuck first mentioned that he was a timebomb on PE’s 1987 song “Timebomb”, where he says, “Look out y'all, I’m a timebomb ticking”

PE’s DJ at the time was Norman “Terminator X” Rogers

A classic line and one of the best of Chuck’s career. He simply means that he doesn’t rhyme just to put words together or hear himself talk, but as a means to political and social change

Here is an image of Chuck D; rendered by Rap Genius editor HaringDMC. He has inscribed the drawing with his quintessential line: “I don’t rhyme for the sake of riddlin'"
http://www.flickr.com/photos/66530616@N08/8507961404/in/photostream

One of the major recurring themes of this album is that the authorities are frightened of Chuck and accuse him of having a gun, when what they are actually scared of are his words

This lyric is partly a callback to the song Public Enemy No. 1 in which Chuck says:

I’ll show you my gun, my Uzi weighs a ton, because I’m Public Enemy No. 1

They of course followed up with the song Miuzi Weighs a Ton which had even more explicit gun imagery. This kind of gun talk (and the fake Uzis carried by the S1Ws) had the mainstream media shook for a while. But the guns weren’t real whereas the militant political message (like their support for Farrakhan and Assata Shakur) was

On the other hand, if you look closely at the “Miuzi” 12" sleeve you can see several members of Public Enemy’s “5-0” Posse holding pistols

Chuck gives the lie to the idea that just because his politics are Afrocentric, that he is only talking to black people

Chuck D was an ancient-by-rap-standards 27 years old when this album (the classic It Takes a Nation of Millions to Hold Us Back) came out, well past the age of hooliganism

Chuck, due to discrimination against his race, is living “low” — on the low end of the societal food chain. He jokes that this puts him “next to the bass” — i.e., near the low frequencies in the musical spectrum

These are the most famous words spoken on record by PE’s “media assassin”, Harry Allen. Allen now has his own (very good) blog with that name

Chuck’s “98” is his Oldsmobile 98 car, which he has praised in song before

The Roots would expand on this line in their 2006 song “False Media”