Interesting thoughts Mansun. I am inclined to believe as most have stated: Tolkien did not "steal" from the Bible. True, aspects of it can be seen in his work, but that does not imply plagiarism or stealing. This thread gives some excellant thoughts about the topic.
Metareferences and Intertextuality.
Now, as far as specifics are concerned, I can see some. There could be strong cases made that Gandalf, Aragorn, and even Frodo were Christ-like. A case could even be made that Elrond was also. I wouldn't initially make that connection, but links between the two do exist. Although, I don't think any of them could really be said to represent Jesus.
Although, I do say otherwise about Melkor. He, in my mind, exactly represents Satan. Sauron does also. Their aspects of being good at one time, falling into evil, often appearing likeable or pleasant, but deeply desiring to hold and corrupt everything sounds extremely close to the story of Lucifer that I've heard. In my mind, Melkor and Sauron directly represent Satan.