Lyric discussion by ccjockey 

Cover art for Let The River Run lyrics by Carly Simon

The song is about making the most of chances given to us.

"The New Jerusalem" is a way of saying making to the a promised land, whatever that may be for each of us.

It talks about the nervousness we all feel when facing a new situation in life. The uncertainty that makes us ache deep down. The "dark'ning dawn" is another way of saying "it's always darkest before the dawn", meaning our uncertainty of a change is usually at its worst right before we go into it.

My Interpretation