The following comments are ones I've found on the Internet. They're from fans, just making guesses, etc.
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I'm surprised I haven't heard more about the seemingly clear Biblical references. For instance, Jacob=Israel, Jesus=the new Israel. Jacob is the Christ figure who willingly sacrifices his life because he knows that that His sacrifice is ultimately the way to "win."
In Christian theology, Satan thinks he has won by killing Jesus, but in the end, his death is the very thing that defeats Satan/evil. I'm thinking we haven't seen the last of Jacob.
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mystery island guy was playing Ben right from the start, it was his plan to manipulate Ben all this time to the point of revenge 35 years later, so that he was willing to kill Jacob! Mind melt!!!!
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It seemed to me that Jacob was waiting for this to happen. He even seemed to antagonize Ben a bit by saying "what about you?". I suspect Jacob needed to be martyred - I just cannot come up with a reason why? Does he have some insight to a "loophole" as well? Any thoughts on this?
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One more BIblical angle: the fade to white with a black "LOST" vs the previous fade to black with a white "LOST" points to what happens when FAITH ... Jacob - ultimately, beloved Israel was created when the Spirit of God changed Israel's hardened hearts - see Ezekiel; from this line came the ultimate GRACE that would willingly allow himself to be killed by sinful man - BEN. .But this fulfilled the LAW, and satisfied it for all time. Thus, all who believe in that GRACE are saved from the wages of sin as determined by the LAW (which is not bad, but necessary for helping lead people to GRACE / salvation by FAITH) ... and the Island is the NEW CREATION established by the fulfillment of the LAW by GRACE; this ultimately creates fellowship and "togetherness".
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Jacob and Anti-Jacob (for lack of a name) are Gods. What type of Gods (possibly Egyptian) isn't really important to this theory. These two Gods have been warring/arguing over a fundamental question about humanity for a very long time. That question is whether humanity is inherently corrupt and evil or inherently good and pure? To finally figure out who is right on the matter the two Gods decided to put together a test. They would offer humanity a perfect place, a miraculous place, their very own Garden of Eden (The Island). And for generations the Gods have been "calling" groups of humans to the island to see how they will react in this setting. Will they live together in harmony and understanding in the midst of a setting where anything is possible or will they resort to violence and decit and even attempt to control or harness the Island for their own purposes (The Dharma Initiative). So far every group of people that have come to the Island have went the way of the bad. But Jacob doesn't want to give up on humanity. This is why we saw him bringing yet another group to the Island in the passengers of the Black Rock in the first scene of the finale. None of this theory was better emphasized when our castaways ran into a couple of their long lost friends. The scene where Rose and Bernard talked about being "retired" and berrated Sawyer and friends about how they are always fighting against somebody was a key scene in my opinion. Rose and Bernard symbolize the hope that humanity can be good, and can forget about the fighting.
P.S.
I think the reason Anti-Jacob needed some sort of "loop-hole" to kill Jacob is because one God cannot kill another God. They can only be killed by the hand of a human. This is why Anti-Jacob said "You wouldn't believe what I had to go through to get here" (or something close to that). Anti-Jacob has had to manipulate everything we've seen just to get to this point. All to get Ben into the mindset of wanting to kill Jacob so that Ben would do what Anti-Jacob could not. Interesting stuff...
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1. Evil Locke = Christian's Ghost = Other Dead Souls of the island = Mystery Man in Black from the beginning of the episode = SMOKE MONSTER. It all seems to point that way. Since John is not John and the monster can take the form of any of the people who have died on the island.
2. "They're coming" from Jacob means that Jack's plan worked and that the rest of the Losties trapped in 1977 will catch up to the present. That's why after Jacob got kicked into the fire it flashed back to Juliet and the bomb.
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Jacob is Christ, the "other guy" is Satan. Satan can not kill Christ, so he needs someone else to do it - Ben is thus Judas. Jacob/Christ gives man free will - you must decide. Ben/Judas kills Jacob out of spite - wanting his own way. Jacob/Christ lets himself die because he knows a greater magic/loophole a la the Lion the Witch and the Wardrobe.
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