The character of Jacob may be the hardest nut to swallow. Was Jacob a god, a devil, a spirit, a smoke monster or an illusion?
Jacob came to the island in his mother's womb. Claudia was a woman in the classic Roman period (27 BC to 400 AD). She was shipwrecked on the island. She was separated from her ship crew. she was befriended by an island woman, who midwived the birth of twin boys. Then the island woman (CrazyMom) killed Claudia. CrazyMom then raised Jacob and his brother.
From what we were shown, CrazyMom was the only person on the island when Claudia's ship wrecked during a storm. We do not know her back story or how long she had been the island guardian. However, she grants Jacob and his brother a form of eternal life and she set a rule that neither could harm each other. CrazyMom was like a lighthouse keeper. Isolated, alone, but with a
specific important job to do, one that apparently she was either chosen
or manipulated into taking.
There was a growing consensus that Crazy Mom may have been human at some point. But on the island, enlightenment changed her being into a semi-god status. She was probably tricked into becoming the guardian. She needed to trick someone to take her place, and children are easier to manipulate. Only when she could confer her powers onto another being (like Jacob), could her job be complete and she could pass on (to next life, rebirth, etc.) So being a guardian is not all it is cracked out to be. The parallel with Desmond and the button is the best way to look at this theme. You believe you are doing something important and good - but you grow weary and tired of your obligation, so you also want to pass it on to someone else, so you can achieve your personal peace.
Crazy Mother kidnaps Jacob and MIB and raises them as her own. She sets the rules. The children cannot harm each other. But we will learn that there are no real rules on the island.
MIB
grows weary of the island and goes to live with the surviving Romans, who are
tapping the EM Life Force in an attempt to “go home” or leave the
island. MIB has contempt for the humans, but needs their knowledge and technology to break CrazyMom's rules.
Crazy Mother is upset with MIB, and kills all the Others,
which makes MIB mad with rage so he kills her. In his own rage over the
death of his alleged mother, Jacob kills MIB (or destroys his soul) by
throwing him into the Light Cave where MIB is transformed or released
into the smoke monster. This transformation apparently binds Jacob and MIB to
eternity on the island, together.
Jacob views the island as home
and needs to be protected; while MIB views the island as a prison. As
the protector, the leader, Jacob sets “the rules” between themselves. In order to ease his mind, he creates a "game" to play with MIB/Smokey which is the manipulation and destruction of lost human souls.
CrazyMom called the shipwreck survivors "people,"
like it was a derogatory term. MIB also called the people brought to
the island in derogatory terms: people always "fight, destroy and
corrupt." But Jacob, who was the only person allowed to bring people to
the island. Jacob remarked it all was "progress" in some grand plan
between Jacob and MIB. But it appeared that for hundreds of years,
people brought to the island "served" some vague purpose.
Which leads to the strange behavior of Jacob. If it is true that he continues to bring people to the island (like CrazyMom did to find her successor by shipwrecks?), as a demi-god why did he need people to build temples or Dharma stations? Likewise, why would he need to leave the island to recruit in order to protect it? Besides, that would prove MIB was right: there was something "across the sea." But maybe bringing people to the island for centuries was all Jacob's cruel, new game with his brother, that "lowly people" are bad and their CrazyMom was right. However, "across the sea" could have used as a metaphor. It could mean across the galaxy, the plane of existence, the after life or dimensions.
Jacob had the ability to leave the island and "touch" candidates and manipulate man or nature to get them to the island, so there was no logical reason why Jacob needed an elaborate plan was to find a successor: he could have kidnapped a person, made him guardian, then flee the island. There was no need for an elaborate, centuries long, twisted tale of treachery, worship and murder.
The only conclusion is that Jacob never "left" the island, per se. If he could not physically leave the island, then he would need "help" from the people he brought to the island. Help him to do what?
We assume that when MIB killed CrazyMom and Jacob killed MIB, Jacob's soul was "imprisoned" on the island forever. But after his guardianship was secure, Jacob did leave the island so the concept of Jacob being trapped on the island would be incorrect. We also assume that MIB is also trapped on the island by being a smoke monster, but we don't know if that is true.
One interesting discussion point was why Jacob or other demi-god on the island need people to build huge monuments or temples. Or why MIB/Smokey needs a dead body in order to take human form.
The island powers do not enable the guardian to create mass - he simply can influence people. Jacob seemingly can't just blink, and presto - we have a lighthouse. So proponents of "the Genie theory" that island guardians could create anything with a blink of an eye surrendered with this explanation. If Jacob, MIB or smoke monsters cannot create objects or things out of thin air (or in nature with fundamental elements), then that could mean that they themselves have no cohesive mass - - - that they are truly spirits seeking a material world.
And even after Jacob's "death" he created himself as a man and as a young boy to interact with people still left on the island. So if Jacob could re-create his spirit into various forms, then one could assume that he could have done that before Ben stabbed in the statue. And we know that MIB is the smoke monster who can create various human forms, including Flocke.
We have been told that Jacob was the one who has been bringing people to the island. Was it was not for MIB's sake? One explanation is that Jacob accepted the fact that he caused a cascade of events that led to both his CrazyMom's and brother's death. His world had ended. He was left with a substitute brother, the smoke monster. He was looking for a candidate so he could die (his punishment) and rejoin his real brother in death, but he had not found one person who would "accept" the position as guardian. So there had been a complex con-artist adventure story under the guise of emotional brainwashing to beat down Jack to accept the guardianship.
But is the real island conflict simply that MIB's ghost does not want Jacob to scheme his way off the island by death; he wants to continually punish Jacob for what he did to MIB by keeping Jacob on the island for eternity? Except, MIB's "loophole" was a means to actually "kill" Jacob - - - to break down the barrier of god-like status with the lowly human beings brought to serve him. The means of leaving the island was an act of betrayal, just as MIB's death was caused by an act of betrayal.
In one respect, the island also served as a prison for the 815
characters. Part of them were trapped in the island drama for no
apparent reason except to free Jacob and MIB from their servitude to
some unknown higher deity. Perhaps, with Jacob and MIB's island deaths,
they would be awakened in their own parallel sideways world that their
real mother created for them.
But what was Jacob supposed to represent in the series?
The boogie-man? The man in the shadows? The puppet master? The means to the end?
If one looks at the full storyline, the Jacob character is the most important element to the island conclusion - - - but at the same time the most irrelevant character in the 815ers after life reunion.
In one respect, Jacob was a psychopath. He kidnapped, cajoled, manipulated and killed people he tricked into coming to the island. He stalked his candidates from a young age. From the light house wheel, at least 340 people were brought to the island and did not "pass" his test to become the next guardian. If one did not become the guardian, MIB/Smokey disposed of them. There is a tag team mass murder dynamic.
Why would someone he vowed to protect the life force extinguish so many people who contained the life force? It makes little sense. As MIB told Alpert, Jacob was "the devil." In certain respects, that is the truth. Jacob's island and Jacob's rules created hell for the people brought within its sphere. Whether this hell made the characters better people is debatable. Most never changed or were redeemed in the sense of valor, heroic actions or moral absolution.
Jacob is not mentioned in the sideways world. He is not seen. He is not referenced. He is not part of anyone's consciousness. He is a nullity.
Then we get to the unanswered question: was Jacob "real" in the first place? A human being that lives for thousands of years is not a normal human. An entity that grants immortal life to Alpert, but cannot reincarnate his dead wife, but create her image is a cruel master.
It may be that CrazyMom was the psyche of a messed up individual or the personification of an evil soul reaper. Jacob could be that supernatural grim reaper.
But the series did not dwell upon the religious overtones of right, wrong or ultimate judgment. Jacob did not judge people, per se. He merely drafted them as candidates, players in this island game of chess with MIB, and let them find their own way to life or death. The idea of a guardian with no guidance is strange. One with ultimate power who refuses to use it to better mankind is not a hero.
Jacob's death did not seem to be a heroic gesture. It seemed like a slow suicide pact coming to bear. Jacob's death did not seem to change anything on the island. Flocke was still Flocke. The faux crisis of Widmore's attack was still present. The characters running through the jungle without a clue what to do continued on endlessly. It took five and three-quarter seasons to get four candidates around a campfire with Jacob's spirit to have one person, Jack, accept the guardian position. It seems like the worst goose chase or snipe hunt in history. And with Jack taking over for Jacob, how does that transform a smoke monster into a mortal being? Jacob's brother was already dead. Jacob himself was already dead. The people on the island had no real means to leave so the island would protect itself by sinking to the ocean floor.
Jacob as a character has little value in trying to figure out what was the big premise of Lost. In order to get to a quick wrap up, the Jacob-MIB conflict was thrown together as some focal resolution point. But even that conflict was erased by the meaning of the sideways after life. So what if the Lost characters were already dead? Did Jacob, in any way, help them on their after life journey? One could only argue that Jacob brought together people on the island not for his benefit, but to allow a host of lonely people to "die together" in the after life. If that is the takeaway point of the series, it seems 99 percent of the stories were hollow and shallow.