After watching 'across the sea' I have decided that all of the religion references are a red herring.
When I first saw the light that lead to the islands 'heart' (or source) I didn’t know what to think. A little cheesy. But then when we saw Jacob's brother inside the well I thought to myself 'there's nothing mystical about it'. What we are seeing is the writers way of displaying high electromagnetic activity in a way that we can visibly see it. Jacob’s fake mum and her predecessors all believed that they are doing what they are doing 'to protect it' because they believe it is mythical or religious or whatever. It’s the same as me showing an ancient Egyptian electricity, the first thing he would think of is to worship it (or me for showing him it like Jacob does his mum). That which man doesn't understand he puts down to an act of god. I believe all of this Egyptian crap and biblical references are one big red herring as to what the island really is, which is just a place on earth where strange things happen because it rests on a high amount of unpredictable electromagnetism which have altered the fabric of space/ time due to various events we have seen throughout the past 6 seasons.
Points to support this.
1. ‘Across the sea’ has (unsurprisingly) raised more questions than it has answered.
-Who is Jacob’s fake mum?
-Where there people before her?
-How did she make it so Jacob and MIB couldn’t harm each other?*
As she said to Jacob’s real mum ‘the more I tell you the more questions you will have’. This is the writers way of telling us that the mythology is done with. There’s 2 ½ hours left of lost and it will focus on our losties, not mythology.
[*Here’s a little thought, what if when Jacob’s brother fell down into the ‘heart’ he died. End Of! Smokie, which already existed (hence Jacob’s fake mum’s comments to him about what lies down there) and when we see him as MIB he is just ‘appearing’ to Jacob as he does other people. Maybe Jacob could kill his brother but the thing we see now is not his brother. However I am aware that smokie is still saying he wants to leave the island so I could be wrong. Unless Jacob’s brother was ‘claimed’ before he died.
I do firmly believe that Jacob's brother is dead though, hence his body decaying in the caves with his mothers. It's just what is John Locke that's confusing. Is he Jacob's brothers mind as the smoke monster or something totally different???].