"My aunt once said the world would never find peace until men fell at their women's feet and asked for forgiveness."
"'That's right!' Dean said. 'Yes!' Shearing smiled; he rocked. Shearing rose from the piano, dripping with sweat; there were his great 1949 days before he became cool and commericial. When he was gone Dean pointed to the empty piano seat. 'God's empty chair,' he said. On the piano a horn sat; its golden shadow made a strange reflection along the desert caravan painted on the wall behind the drums. God was gone; it was the silence of his departure..."
-On the Road-Jack Kerouac-

Maybe I should give my interpretion of the second quote. If Shearing is God, then his creation is music. The instruments remain behind after Shearing leaves. The shadow cast on the wall is God's instrument. If God makes music, the instrument is left behind to reveal to the caravan that God is present. The group found that God does exist because of their journey around America.
On the trip to New Orleans, Sal was talking to Dean about his dream of being chased in the desert by something. He figured out it was death chasing him through his desert of a life. They were wanderers, lost in a vast desert; nomadic. These guys are surviving on scraps and they don't care. Can you imagine living such a life? I wouldn't mind! Life isn't 9 to 5! Life is out there. You have to find it and realize that what makes you happy is life. Grab it and hold on to where ever it takes you. Good luck!