Whenever I look back
On the best days of my life
I think I saw them all on T.V.
I am so homesick now for
Someone that I never knew
I am so homesick now for
Someplace I will never be
Time won't let me go
Time won't let me go
If I could do it all again
I'd go back and change everything
But time won't let me go [ Lyrics from: http://www.lyricsmode.com/lyrics/b/bravery/time_wont_let_me_go.html ]
I never had a 'Summer of 69'
Never had a Cherry Valance of my own
All these precious moments
You promised me would come in time
So where was I when I missed mine?
Time won't let me go
Time won't let me go
If you gave me back those years
I'd do it all better I swear
Time won't let me go
Ba ba ba ba ba...
If I could go back once again
I would change everything, yeah
If I could go back once again
I'd do it all so much better
Time won't let me go
Time won't let me go
If I could do it all again
I'd go back and change everything
But you won't ever let me go
Sam is talking about his past and how he couldn't have a cherry valence and some precious moments. He's regretting about missing all the moments. Of course it's a beautiful song because not only his but it also depicts many of ours lives( and it's my favorite song! ).
When you get old, like me, almost all you have left in life is regret. You stand looking at the past, and every opportunity that passed you by, and realize that you are a victim of time. Those mistakes are forever, and you will never have the opportunity to repair them, because you are dying.
He's looking back on all the times he could change and everything he never had that he wants now, wishing he could change the past. He knows however, it's impossible.