We know that Jacob brought the LOSTies to the Island, and before that, he brought the Black Rock ship, and before that, he brought other people — the ones who came, fought, destroyed, and corrupted, in the words of the Man in Black.
The big question, of course, is why is Jacob bringing all these people to the Island?
One thing we know about the LOSTies is that, as a group, they have an extraordinary number of Daddy issues.
What if that were actually the reason that Jacob chose them?
And if that were the case, then why?
Suppose that Jacob himself has Daddy issues. Suppose, also, that Jacob is on the Island not because he wants to be, but because he has to be. There’s a hint of that, I think, in Jacob’s oddly impassive reaction to the Man in Black when the MiB said he wanted to kill him.
Combine the two ideas: Jacob having his own Daddy issues, and Jacob being stuck on the Island for centuries against his will. That suggests some sort of crime and punishment, with the Island being a place of exile, a prison. Because of the Island’s strange time-warping properties, Jacob’s sentence spans far more than a normal single lifetime.
Such a long sentence implies there must have been a horrible crime. And the worst crime that exists that involves Daddy issues would be patricide. Maybe, like Oedipus Rex, Jacob — way back in his original life, eons ago — had killed his father.
And now he is stuck, seemingly forever, on an Island prison. Maybe there is only one way for him to end his sentence — by restoring some balance to the world by doing something that would counteract his terrible crime. Only in that way could he atone and be forgiven.
Maybe Jacob’s task is to heal people who have been harmed by terrible rifts with their fathers. More precisely, maybe he is trying to show them how to heal themselves. Success in this task would be the only thing that could release him from his centuries-long sentence.
Perhaps he has tried, and failed, with all the previous groups he brought to the Island — which is what was frustrating the Man in Black. But the current LOSTies do seem to be responding to Jacob’s guidance, and many of then have, while on the Island, come to terms with their Daddy issues and grown beyond them.
Two possible holes in the theory: (1) If the Island is a prison, how did Jacob get off so many times? and (2) What is the role of the Man in Black?
Perhaps Jacob was able to leave only when certain conditions were right, and only for the purpose of choosing people to bring back. As for the second question, maybe the MiB was a participant in, or at least an accessory to Jacob’s crime. Since the MiB does not believe that Jacob will ever be successful in his task, maybe the MiB sees killing Jacob as the only way to bring his own long exile to a close.
And perhaps Jacob could not succeed in his task of guiding enough people beyond the Daddy issues which had warped their lives. At the end of “The Incident,” when Jacob told Ben that he had a choice — he could choose to listen to notLocke, or he could choose to walk away –Ben was so caught up in his Daddy issues, projecting onto Jacob all the rejection he had felt from his own father, that he could not make the right choice. Ben, at that moment, could not get past his Daddy issues, and for Jacob, that meant both failure, in his task as a guide, and death.
Picture of Oedipus Rex from an 1896 production, via Wikipedia