THE JACOB ALTERNATIVE

There were a few absolutes in regard to Jacob.

1. He was immortal.
2. He was the island guardian.
3. He was the only person who brought people to the Island.
4. He had the ability to spy on people throughout their lives.
5. He had the ability to go off the island and touch his "candidates."
6. He gave the people brought to the island free will to make their own decisions.

What purpose did Jacob truly serve?

Most of the main characters in the series had no religious consciousness. Most were not devoted or true followers of any faith. Many, like Charlie and Hurley, grew up in religious families but had waned on their observation.  Many, like Eko and Sayid, referenced religion in the daily routine but acted in the opposite manner in their real lives.

LOST could have tackled the idea of sinners without religious observation by the background character of Jacob.

What if Jacob was not just the island "guardian" but a guardian angel?

Jacob dressed in white, which is symbolic of angels.  Instead of the scythe of a grim reaper, Jacob used a lighthouse and the touch of of hand to guide lost souls into eternity.  He may have been one of the spirits entrusted with guiding the souls of the no longer living to the other side.

Unlike the devils in literature who approach their grim duty with detachment or even malevolence toward sinners,  Jacob may have tried to "save"  those about to cross over.

He did not give solace and sympathy to those he brought to the island, but an opportunity to resolve lingering issues in a person's life,  or even a chance to make amends. He does not directly lecture these lost souls but gives them a complex environment in which to re-live their troubles in a different setting to see if they can resolve them.

Jacob would give the island visitors the opportunity to believe in something, including themselves, in order to reconcile their confusion and pain attributed to their lives on Earth.

It is not purgatory, but a diversion program toward the afterlife. 

As we learned, there are people who did not find what they were looking for on the island. They became trapped souls (the whispers) like Michael. In Michael's case, he may have been brought to the island to reconcile his abandonment of his son. But in the end, he made things worse by killing innocent people in order to get his son back. Michael failed to reach his afterlife.

Those people who reached the sideways church did reach their afterlives. They may have reached the church because they fulfilled something missing in their lives, such as true friendship or love, which only came about due to the events that Jacob created on the Island. Each found a new purpose and reason for living by passing the island challenges. In a clever way, Jacob allowed each person to help themselves without sermonizing their faults. That is what Clarence did to Jimmy Stewart's character in It's A Wonderful Life.