Not all christians share the same beliefs. what, in your opinion, are the most important beliefs in christianity? what defines a person as christian or not christian?

You either are, or aren't. There is no grey area with this.

Explanation:

Ok, so here's the deal. I'm a Lutheran (Protestant) and in my opinion there are very few requirements to be a Christian. You simply have to believe that Jesus was the son of God himself, and that he died for our sins and rose again. (For God demonstrates his own love for us in this. While we were still sinners Christ died for us. (Romans 5:8)). That is the basis of Christianity. It does not require you to go to church every Sunday, go on mission trips to Africa, or donate every dollar you have to charity. It just means you have to give your life to Christ and do his works, IN HIS NAME.

I hope this helps and if you have any other questions just let me know

determination