Mysterious man with Jacob explained by Kelg

My theory is that the man with jacob at the beginning of the finale of season 5 (call him mister X) comes FIRST in the form of Christian Shepherd THEN as John Lock, as seen in season 5.

Here is why:

Christian is dead when Oceanic 815 crashes on the island. Jack then sees his father on the island. Also, in the bonus features in season 4, it shows Christian telling vincent to "wake his son up" which ends up being the first scene of Lost. Mister X (this time in Christians body) is the one driving the plot.

Then, in season 5 " this is death " episode, Lock meets Christian (mr X) in the well. He shows him how to bring the oceanic 6 back on the island and also tells him he HAS to die. this is so that later on he can transfer to Lock's body.

When Eloise hawking tells Jack to put something of his father's on dead Lock, and he choses shoes, this is because there needs to be a link between Lock and Christian so that Mr X can transfer bodies.

Back in the well, Lock has a broken leg and asks Christian to help him up, but he says he can't do that. This is probably linked to the fact that Mr X will soon become him and for some reason touching him will spoil things; but I haven't thought out further details on that.

The reason why Mr X picks Lock is due to the so called "LOOP HOLE" Mr X and jacob were talking about. I think that maybe only the leader of the others can kill Jacob and since Richard names Lock leader, he is the candidate.

I believe that Mr X is the brain behind the whole plot, and new Christian and new Lock's actions are what leads up to Mr X achieving whatever it is he wants to Achieve.

Thats what Season 6 will come down to, I think.

Ps. I think this is the tip of the iceberg but who knows, maybe eloise is on it , etc...