Murder is a tough thing to digest, it's a slow process
And I ain't got nothing but time
For many people, it takes a long time to come to terms with murder. By saying he has plenty of time, he tells you he has no issue with killing someone.
This is also a demonstration of his ambition. By suggesting “i aint got nothin but time” he envisions himself being around for a long time, even before he began.
It’s also a double entendre if you see it as not only you get jail time for murder if worst scenario, you get caught but most of the time you get a life sentence. So yeah, only thing you got left is time.
To help improve the meaning of these lyrics, visit "Dead Presidents II" by Jay Z Lyrics and leave a comment on the lyrics box