When a Blind Man Cries Lyrics

Lyric discussion by Ereinion 

Cover art for When a Blind Man Cries lyrics by Deep Purple

it's one of the saddest songs i've ever heard. it's so short yet it conveys so much sorrow, especially the last line: "When a blind man cries, Lord, you know he feels it from his soul."

i think he's shut himself off from the rest of the world. but what i can't figure out is why he calls himself a blind man...