It's getting harder to visit office water coolers without hearing the whispers of the "Lost" disciples who are bracing for the end of the world as they know it. The same thing is happening during coffee hours in religious congregations of every shape and size, which is a testimony to the complexity of the religious themes and symbols embedded deep in the show's mythology. Tough theological questions have circled the island of the castaways ever since the fateful crash of Oceanic Flight 815.

Do absolute moral truths exist? Do good intentions ever justify evil acts? Does real love always lead to self-sacrifice? Can faith and reason coexist or even mesh? Can people change or are they doomed to commit the same sins over and over? What does it mean to be saved? To be delivered?

Some questions are more plot specific. Biblically speaking, what would happen if a patriarch named Jacob was killed by a brother who may or may not be named Esau? Why do some of the island's inhabitants occasionally speak Latin? What is the significance of the fact that most of the characters had horrible fathers? Where do the female survivors get all those tight-fitting tank tops?

" 'Lost' is a religious parable with obvious biblical references trying desperately not to be a religious parable," according to Catholic writer Roberto Rivera y Carlo, who is best known for his work with the evangelical apologist Charles Colson.

"The religion that has been most straightforwardly stated on the show has been straight-no-chaser Christianity. People pray like evangelical Christians or faithful Catholics. There's no kumbaya-style religion. … Ultimately, 'Lost' is an exploration of free will versus determinism or human freedom versus predestination. Take your pick."

Let's see, the plots involve hope, doubt, reason, freedom, sin, virtue, salvation, damnation and seekers striving to find empirical evidence to back their often agonizing leaps of faith. No wonder there is a central character named John Locke, along with others named Milton, Hume, Rousseau and C.S. Lewis (a Charlotte Staples Lewis, this time around).

The men who have been running the program for most of its life -- Damon Lindelof, who is Jewish, and Carlton Cuse, a Catholic -- have called themselves "men of faith," while confessing that "Lost" has become a "mash-up" of their favorite Bible stories, college philosophy textbooks, fantasy novels and movies. Thus, it will be impossible to understand Sunday's finale without wrestling with its final, indeed ultimate, spiritual questions.

"If there’s one word that we keep coming back to, it's redemption," said Lindelof, in a New York Times interview that has caused waves of online fan discussions.

"It is that idea of everybody has something to be redeemed for and the idea that that redemption doesn't necessarily come from anywhere else other than internally. But in order to redeem yourself, you can only do it through a community."

In the end, it's almost impossible to say that "Lost" has one overarching theme, said the Rev. Chris Seay of Ecclesia Church in Houston, author of "The Gospel According to 'Lost.' " However, if forced to choose, he said it's clear that the central characters have been forced to realize that they cannot survive as selfish, isolated individuals -- they must "live together" or they are doomed to "die alone."

However, this also means they have had to confront the reality of their own flaws, he said. Over time, he said, the survivors learned that if they were going to be saved they would have to "fear the evils they find inside themselves more than they fear what is out there in that jungle." That's the kind of message that works in a pulpit, as well as on a large-screen television.

While "Lost" does contain its share of references to Eastern religions and direct references to Christian classics, Seay said recent episodes have reminded him of a defining event in the Hebrew Bible -- the Exodus of the people of Israel out of captivity in Egypt.

"In a way, these years on the island have been their time of wandering in the wilderness," he said. "They've had to learn how to live in forgiveness with one another, to face their own sins and find some kind of healing and some hope for the future. ... You have to ask, what would a promised land look like for this set of characters?"