If you have not experienced Larry Norman's work, you owe it to yourself to find his recordings and indulge.
This LP was the third in an trilogy of concept albums. It was released in 1976 and was preceded by "Only Visiting This Planet" and "So Long Ago the Garden."
I cannot even begin to explain the phenomenon that was Larry Norman. I strongly encourage you to read up on him. HERE is a link to the Wikipedia article regarding this LP, and HERE is a surprisingly in depth article on Larry himself.