For in the wisdom tradition I was raised - the framing of the question was in itself part of the answer. All of us have a message. A message to ourselves, a message to the world. The message is encrypted on our psyches - it is our very souls. However, so often we become messengers who forgot their message.
Life is about recovery - it's about recovery of memory.
The PBS special skims the surface as is the nature of that kind of medium. I hope - is far deeper and gives you the tools, conceptual frame and experience of reading that will allow you to make it real in your life. Briefly however, religious comes from the Latin word ligare - meaning connectedness. So if religion is about connection, the book is religious. Tragically of course, religion has become all too often, a dividing line instead of a uniting umbrella.