I'm starting to think that really depends, Haejin.
There is some oddly similar deities to the Christian idol of Jesus and his divinity story that predate the New Testament account of Jesus.
I'm not sure if it would be fair to find those similar deities and look back at the history of the Christian cult and perhaps find that at best, we may have a revolutionary people under Roman rule that created a Jesus story later based on deities of the Greek and Roman pantheon.
I really am not sure right now because I haven't gotten that far in Karen Armstrong's book.
But I don't think it's entirely unfair to look at older myths, find the similarities and then compare them to the story of Jesus. I think what you might find interesting is that.
http://jdstone.org/cr/files/mithraschristianity.html
Saya can confirm this I'm sure. She'd know better than me. I've just heard that these stories were incredibly similar.