Lyric discussion by karvinism 

Cover art for Genesis 3:23 lyrics by Mountain Goats, The

I always figured the guy was (un)dead.

Hence the pause in "I used to live...here". Hence he has to "break the lock on [his] own garden gate," it's a cemetery. Hence he lies out looking at the stars "like teeth in the mouth of a shark," he's lying in an open grave. Hence "hope they're better at it than I was" - not living in this particular house but living in general.

Clearly, he should meet up with the guy from "The Cool" and have adventures.