A Tale of Two Christians from Two Timelines, On One Island as the Nexus Between by JohnConstant69

How come we've seen Christian decked out in full suit and tie, his burial clothes, and then also Christian in more casual wear?

How come we've seen Christian barefoot, but then also wearing Jack's shoes?

How come Christian already seemed to be deep in the jungle, alive, walking around, directing Vincent to help Jack, only a few seconds or minutes after the crash?

Is Christian continually changing his wardrobe and choosing to go barefoot at times?

I submit it because there's 2 Christian Shephards on the island.
One from the traditional 815 timeline, one from the ALT universe timeline.

Remember that if you die on the island, you are alive in the ALT. So the hint was: what does it mean if you die in the ALT? Obviously, you are alive on the island.

We know Christian died in the ALT, and is missing. Where did he go? The island.
When Hurley came upon Jacob's cabin in the season 4 premiere episode "Beginning of the End", people noted that Christian Shephard was rocking back and forth in the chair, with Jack's white tennis shoes on. But! Who was the mysterious person at the window peering out at Hurley? Some said it was Locke, some said it looked like Desmond's eye, even Jack's eye.
I submit it was--Christian Shephard's eye. Up until the ALT, people didn't even imagine the idea that there could be 2 of something.
So I'm saying both Christians from both realities were in the cabin, hashing out their differences, or possibly working out their plan, depending.
This also solves the "how did Smokie get off the island to appear to Jack at the hospital, I thought Smokie was trapped on the island" mystery. It wasn't Smokie. It was Christian from the ALT.
I would also submit that Charlie appearing to Hurley was from the ALT.
Its one reality encroaching on another.
Wet Walt? Wet Walt was from the ALT.. possibly the underwater island. Wet Walt from the ALT.
Characters talking backwards? (Walt, whoever phoned Kate, Locke in the promo, etc.) from the ALT.
Wet Locke from the sub? Wet Locke from the ALT.

I don't know if the two Christians are both evil, both good, one evil/one good, or neither. They could be like a proxy for Jacob/MIB.

Remember the deleted scene from "Shape of Things to Come" from s4? Two Bens? One lying in the desert where he landed in Tunisia, and another one already back from some mischief on a horse, finding his secret stash. Perhaps that was deleted as a "taste of things to come" because they didn't want to let the cat out of the bag that early on.

There's always 2 of everything, to steal a phrase from LOST's "sister-show", Fringe.
I submit that one of the two Christians (or both) was trying to influence events on the island in such a way to impact the end game. Sure, MIB may have wanted Locke to move the island to invoke time travel to prove to past-Richard that future-Locke was special and ready to lead the Others, to get him to leave the island to die so that MIB could pretend to be him and use his credentials to get close enough to Jacob to have Ben take him out. Sure, MIB may have wanted this, but I suspect Christian has an even "deeper magic" to call forth in this plan, knowing that yes, Locke may have to die, yes, MIB may have to rise to power, but this will also make certain events come into play that will ultimately put an end to all this, having it end once, and in a good way.
One of the missing pieces, I believe, to the larger puzzle of LOST, is how a) some things just never made a whole lot of sense, and I'm not talking about how the writing changed, if they planned everything from the beginning, etc. but actual intentional mysteries that didn't seem to add up, and b) there seems to be a vague fog of some other unseen force/power on the island moving about, manipulating things.
I again submit its because there are not only 2 Christians roaming around on the island, but other players and events from the ALT are moving about to influence the end game.

I haven't completely worked out all the kinks of this, but this is to get people thinking and discussing and seeing if we can keep going somewhere interesting with this.

I also wanted to say this fits perfectly in harmony with my previous theory that the ALT is not really an ALT timeline at all, but is a new karmic "incarnation" cycle. In other words, its another go-round for the reincarnated main characters of LOST. The core 815ers are the original reincarnated island gods.
I used "ALT" and "timeline" to make things simpler.
Canton Rainier on the side of Ben's van in s5, right?
If you'd like to read that theory in full (with EXCELLENT interaction from responders), please check it out here:

http://theoriesonlost.blogspot.com/2010/02/core-815ers-are-original-ancient-island.html

Anyways, I am saying, the flash-sideways scenes we are seeing are not occuring simultaneously to the traditional 815-crash timeline. They're occuring either after, or before.

What about the numbers? Locke-4, Hurley-8, Sawyer-15, Sayid-16, Jack-23, Kwon-42. I submit this is how many times they have been reincarnated and have been to the island. It always ends the same, but everything else is just progress. It may also be the number of times Jacob selected candidates and MIB took them out. Perhaps others besides Jacob and MIB selected them, and THIS time, say, Jack's 23rd time, is Jacob's selection. Some of you have cleverly noted that Jack moved from seat 23 in the 815-crash timeline to seat 24 in the ALT timeline.

So how can the two reincarnation/rebirth life cycles occur one before the other, but the island events can include characters from both (2 Christians?) Because the island moves THROUGH time, and space, right? The island is independent/outside of time and space. This makes sense, as it would then be the nexus of not only those timelines/incarnations/circles of life, but the nexus of ALL of them. Like, if Jack has been reincarnated 23 or 24 times now, Jack #12, and Jack #7 could both land on the island and possibly interact with each other.

I don't want to lose anybody here, so this next part will be the most complicated I'll get: about 2 years ago there was a rumor about the season 4 finale saying that older bearded Jin came out of the temple and stopped Locke from fighting with Richard Alpert over leadership of the Others. The big secret was that there were Elder Others in the temple that no one had ever seen before. Aside from people speculating recently that many parts of that rumor were true and played out in season 6 (Flocke beating up Alpert in front of the Others, or that Dogen could be mistaken for an older Jin, from an onlooker far away that didn't know any better)... aside from all that, the theory was that time travel was explaining a TON of stuff, including.. who were the mysterious Others who kidnapped the kids at night, that Eko fought off? Answer: The core 815ers did it. How come the Others had files on the 815ers that seemed to know so many things that people couldn't possibly know: answer? The! 815ers wrote them themselves. How come we heard Hurley's voice repeating the numbers on the french 1988 island landing? answer: it was Hurley's voice, and he recorded it way in the past. How would all these work out chronologically? We think the present time on the show is 2007-2008, but in actuality it is more probably 2014 or something. That would've been the big shocker.. that 90% of the show took place in the past. The flashbacks were just further in the past, and the flash-forwards were just more recently set in the past. The 815ers learned their lesson from all the previous time-loops where they kept making things fail and made things worse, and this time they were manipulating certain events to ensure it all came out right in the end. They were supposed to be much older, and hiding out in the temple, and we would see them all come out and this would be a major shocker.
Obviously, this theory is most surely wrong, but I think elements of it still held some truth:

What if instead of it all being about time travel, and timeloops, its all about the reincarnations, the life-cycle loops, the ALT universes, where people from the other "timeline" have come to the island to secretly manipulate events to ensure a certain end-game.

2 Christian Shephards would be the easiest sneak-peek at this MAJOR reveal. In no way could you show that any other major character was doing this until possibly the final episode.

If you're still here, thanks for sticking with me this long. I apologize if it isn't nicely packaged and organized in a linear stream of thought. I know I jumped a little all over the place, but I needed to get my thoughts down here so we can brainstorm and debate and see if there's more to this.

Remember, 2 timelines, one island, 2 Christians.

Let me know in the comments what you think, and even submit more ideas if you feel so inclined.

Thanks!