You 16, you could do 20, come home young
Catch 20 years when you 40? Holmes, you're done
Nas, who is aging, and is almost 40 (38), is saying that when he was younger, he could afford to risk 20 years in the pen, because he would still be about the same age he is now, and still able to live, however now, he is no longer a youth, and if he were to spend 20 years in jail, he’d come out an old man.
Nas talks about it a little bit here:
Holmes is short for homie, home boy, etc…
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