Lyrics:

There was an old man who lived in the greenwood
nobody knew him or what he had done
but mothers would say to their children, 'Beware of Mad John.'

John would sing with the birds in the morning
laugh with the wind in the cold end of night
but people from behind their curtains, said he's not quite right.

John had it sussed he was living the life of a tramp
yes his bed was the cold and the damp but the sun was his friend
he was free

So here was a wise one who loved all the haters
he loved them so much that their hate turned to fear
and shaking from behind their curtains the loved ones would hear.