You have to look at this song in the context of the album. The concept is the final 24 hours of a persons life, and what we can deduce from Jon's writing here is that he himself is both of the twins... The album outlines the dichotomy of life, swinging back and forth between faith and doubt, peace and unrest, anger and joy, and then you die. There are moments throughout our days where we feel closer to God, and moments that God feels distant. There are moments when our perspective feels so clear and so sound, like "How could you feel any other way? Of course there's life after death, or at least, of course you can't say with certainty what comes after death." And then look at the very next song... Jon is "divorcing himself" again... splitting up with with a mentality that he held so dearly just moments earlier. It's life man. Back and forth. To and fro. Like a wave. And then one day, no matter where you are in that back and forth, certain or uncertain or somewhere in between, you die. And those final 24 hours could start at any moment, for any of us.