If you're a "baby boomer" you probably remember "Jonathan Livingston Seagull" very well! This book appeared in the early 1970s when so many of us were searching for inspiration. Loving the uplifting message but without even understanding the religious undercurrents, we embraced it as one of our classics.
It can be read just as a very uplifting story, taken almost literally, but realizing that the seagulls represent humankind. We just want to fly like Jonathan!
Also, though, Richard Bach's deep spirituality is there to be appreciated by those who wish to delve further into that realm. And, in reading it again now, I recognize how much of the experience of Jonathan, and his followers, parallels that of Jesus and the early Christians. Of course, no accident! But when I first read it I was not looking for a Christian message, just inspiration, and I found it. And that inspiration is there as clearly today as it was back then.