As long as the story is well done, as others have said.

Even Star Wars has religious themes.

No one is taking Star Wars from me.

If I’m entertained by something, then find out it has a religious message or origin, it does not bother me in the least.

If it's a good enough story I don't mind. Religion is just a fantasy that too many people think is true. Good writing and art in general comes from many sources of inspiration.

It really doesn’t concern me too much what the source of inspiration is or what the message might be, especially when you consider works of art. Good stories are still good stories. Beautiful music and painting can still move me regardless of their inspiration or historical context. Now, I may choose not to patronize an artist for purely political reasons, social reasons, or because how I might personally feel about the artist. That’s a different issue. I really enjoyed the Narnia series regardless of the Christian influence.

Considering that religion (as does a lot of fiction) arise out of myth and there are common tropes in mythology (Capmbell's Hero with a Thousand Faces), it is probably more common than people realize. In fact, I remember reading an article stating that Tolkien's Lord of the Rings was just as (if not more) religious in its message compared to Lewis' Chronicles of Narnia.

Back to your question - as long as I enjoyed the story (which means the message wasn't too overt or grating), I don't really mind. Even with music, if it is a good tune, I enjoy it.

I remember once my Dad came home with a copy of dianetics, he looked really weirded out when I explained to him that it was primer for Scientology, never saw the book again.

There is so much out there that does include the mythologies in one way or another...

I love Renaissance art, even though much of it is Christian-themed; I love Bach, even though he mostly wrote for the church. If the work is good enough, the inspiration doesn't matter.

Jacque Deride suggests that any text can be deconstructed in any way you please, that the perceived meaning by the reader may not necessarily be the same as the intent of the author.
Taking the idea that a book is necessarily about what a critic has told you it is about is a dangerous idea.
For example it is possible to put forward the argument that the 4 gospels are simply allegorical texts meant to tell the story of Horus in another form and is in fact Egyptian propaganda for a pagan god.
Best to read something for yourself, take from it what you please and reject what does not please you.
No one tricked you, all texts have intentional and unintentional sub texts because writers are human and have conscious and subconscious minds at work when practicing their craft.

If the religious theme was not part of the cover discription and I bought a book from what was presented I'd be pissed and would return it also.

By the same token, I was invited by a friend to go see the movie "the Shack", I knew it was religious in nature but I REALLY wanted to see a big black woman as God. Even tho I don't beleive I enjoyed the theologic view point and the movie.

What, Like Narnia? It did taint it a little...

I avoid people asking me why I return things quickly by using the drop-off box.

No but it's different in UK maybe.

What did she say to you when you said that?

I can highly recommend Philip Pullman's His Dark Materials trilogy - about as anti-Christian as it gets and very readable.

You thought it was fiction didn't you ? If you think religion is fiction then the book should still be fiction in your mind unless something you read got stuck in your head.I don't know if you got tricked or not.

I hope you got your money back.

I've read a lot of Sci/Fi books that contained religious overtones but none that I could say were proselytizing any Xtian beliefs outside of moving the story along. I don't read Fantasy Sci/Fi so I probably never read a book as you describe.

You are not practicing just exploring, absorbing knowledge. Sometimes reading the enemies blueprints you gain more ways to disarm their troops.

And yes you were indeed deceived....no can't say I've ever been deceived in that manner..

Some of Stephen King's books have an underlying religious theme to them dealing with good vs. evil. Even though I don't believe in the supernatural I don't mind it as long as the story is good. If it gets too ridiculous and impossible to believe then that is disappointing. For something to be scary it has to be realistic.

Its all a matter of perception, if you don't see it, it don't really exist!

No not at all