This will be my last ever theory. And perhaps my first good one. ;)
I believe that many of the mysteries surrounding Jacob that remained after the series ended can be explained rather simply: Before his death, Jacob had time traveled, perhaps also to the past, but definitely to the future. A few points I'd like to make first:
- We clearly know that Jacob was fully capable of leaving and returning to the Island.
- We know that Jacob knew more about the Island than anybody, including the MIB, hence his ability to leave the Island when MIB could not. It will never be explained, but we can only assume Jacob understood to some degree how to harness and use the Island's power.
- It is very possible that Jacob was actually the one to discover the Orchid station, and that he was the first person to actually use the Orchid's powers to travel through time. Even though Ben and Locke had no control over when or where they exited after turning the FDW, it doesn't mean that Jacob didn't know how to. Perhaps he figured out a way to control what time period he was sent to when he turned the wheel. Or perhaps he figured out a different way to travel through time. Either way, we have EVERY reason to believe that Jacob was a time traveler, and that this was how he knew so much about so many things, seemingly knew what would happen before it did, knew the Losties destinies, etc. - Because he already saw it happen at some point, or at least heard about it. Here we go...
- First of all, despite what Miles said, I still think Jacob easily could have escaped the situation. We saw him kick the shit out of Alpert. Ben isn't great in hand to hand combat, M.I.B. couldn't hurt him, and Ilana was RIGHT outside. What does this tell us? Jacob knew he was SUPPOSED to die. Perhaps he time traveled into the future and discovered from someone like Frank or Richard, who both left the island and presumably lived full lives, and who both were just meters away from Jacob when he died, that he was killed by Ben on that particular night, and instead of attempting to alter what was "supposed to be", Jacob simply let whatever was supposed to happen, happen. This would really clear up why Jacob surrendered so easily and seemingly just let Ben kill him - Because that's what was his fate.
- This would also obviously explain why Jacob had the Others building the runway at the beginning of season 3. He time traveled to the future and discovered that the Ajira plane eventually flys off Hydra Island, and so he ordered the runway to be built for when that time came.
- This theory also would explain why Jacob and Eloise were working so frantically to get Jack, Kate, Hugo and Sayid back to the Island. Eloise and Jacob were both on the Island in 1977, when the Incident happened, and knew that if they did not get those 4 back to the Island to make sure that "whatever happened, happened", it could cause a potentially catastrophic time travel paradox, with possible apocolyptic type results. This is why Jacob visited Hugo - It was simply the only way to get him to return to the Island. It also explains why he encouraged young Kate and James to continue on their dark paths, why he saved Sayid from being hit by a car, and why he saved Locke's life. They all had work to do, and needed "a little push" to continue on their destined paths. It's what HAD to happen. Perhaps this is why he tells Jack he just needed "a little push", and why he told Sun and Jin to make sure to never take their love for granted. He knew how all of these people's lives would turn out, for better or for worse.
- This could also explain why he allowed Ben to be healed by the Temple, instead of simply letting him die. I heard someone complaining once that if Jacob had just let Ben die as a child, Ben would never have been able to murder him in the future. However, Jacob was a firm believer in "whatever happened, happened", and knew that he could not allow any potential paradoxes. Jacob was willing to give his life for the Island and the greater good, just like Locke, Jack, and Charlie. He knew by letting Ben live, Ben would stay on a path that would someday lead to him murdering Jacob, but Jacob chose to allow things to play out how they were supposed to, instead of selfishly trying to save his own life, potentially at the expense of reality itself. This is more evidence that Jacob simply let Ben murder him.
- This might also explain Walt's situation a little better. If Jacob time traveled to the distant future and saw that Walt was the new protector of the Island at this particular time, he had to make sure that nothing bad happened to Walt. This is the true reason Jacob had The Others kidnap Walt - to protect the Island's future leader from the dangers of the Island, including MIB, who may also have known this vital information. After Michael got the boat from Ben, Jacob allowed Walt to leave the Island. Perhaps he wanted Walt off the Island until The Man In Black was killed. This is a tough one, but this theory does make some sense.
- Another good point in support of Jacob's time traveling is the scene in "LA X", in which Jacob tells Hugo that he must save Sayid, and instructs him to bring him to the Temple. Some people have said that this makes no sense, due to the fact that Sayid ended up turning evil and almost murdering Desmond. But it does make sense if Jacob already knew everything we saw unfold throughout season 6. Jacob knew that if Sayid died, there would be no Sayid on the sub when it exploded. No Sayid to tell Jack about Desmond, no Sayid to sacrfice himself for his friends... you get the idea. He knew that although Sayid was about to take a turn for the worst, that he had to live in order to save Jack, Hugo, Kate and Sawyer.
The following quotes strongly support my theory:
Man In Black: "One of these days, sooner or later, I'm going to find a loophole, my friend"
Jacob: "Well, when you do, I'll be right here."
Many of us simply thought Jacob was challenging MIB at that time, but perhaps Jacob literally knew that when MIB found his loophole, he'd be right there.
Jacob: "It takes a very long time when you're making the thread, but I suppose that's the point..."
This is probably the one statement that gives the biggest hint that Jacob was a time traveler. At the time, we were meant to believe he was talking about his tapestry, but was he actually talking about reality itself?
Jacob: "Jack is here because he has to do something. He can't be told what that is, he's gotta find it himself." Also... "I had to get you and Jack as far away from that Temple as possible. Someone's coming there. Someone bad."
Jacob clearly knew Jack's destiny. And Hugo's. And probably everyone else. Why did he need to get Jack and Hugo away specifically? Because they were easily the two most important people on the Island at that time. Jacob knew that Jack would go on to kill the Man In Black and save the Island, and knew that Hugo would go on to become the next true Protector of the Island, and knew that he could not afford to have anything come close to happening to either of them. He knew MIB would attack the Temple, knew that Kate and Sayid would survive, he KNEW everything. How? Time travel.
Locke, Jack, Sawyer, Eloise, Widmore, Faraday and Desmond may all have some pretty crazy time travel stories, but the craziest of all was the one that was never told: That of Jacob, the Time Traveler!
This will be my last ever theory. And perhaps my first good one. ;)