I'm sorry if this post offends anyone, but I'm ticked off that everyone's assuming Jacob's rival is named Esau (Jacob's twin brother in the Bible). I'm not saying that it couldn't be Esau, but people seem positive that it's his name. Just because Lost does make some biblical references, it doesn't mean that you should assume that everything's related.
Besides, it doesn't make sense. All of the recent mythology points towards Ancient Egypt Relgion: the statue of Tawaret; the twitter updates of a possible ARG focusing on the Ancient Egyptian Religion and the sun god, Ra; Jacob's tapestry; Paul's Ankh necklace; pictures of the Monster vs. Anubis in the Monster's cavern; and heiroglyphs EVERYWHERE, on Ben's secret door, in the frozen wheel chamber, Daniel's map, the temple walls and chambers, Ajira Airways,even the countdown timer in the Swan Station and the Lost Experience, which have been around since Season 2. It just don't see how all of this Egyptian mythology connected to Jacob would somehow be related to Christianity in that kind of way.
(again, not trying to offend anyone)