Remember when Christian says that there is no "now" here? Well we've seen a lot of theories linking the light in the church to the light of the island, and I buy that concept. I think the light of the island/electromagnetism/heaven is all the same, and that's why the island has to be in its own little bubble of space/time.
That being said, the island has a special relationship with time. It is very fluidic there, and I think this "no now here" thing can actually solve quite a few of the mysteries in the show, including the bird that flew over Hurley's head screaming the name of his future master. I mean Hurley is one day going to stand in the water that flows into the light cave and drink the jacob-making liquid. Then he lives for thousands of years (maybe) taking care of the island.
Then maybe he chooses to go around in time wherever he wants. I mean the Hurley bird was never really explained as it was basically an inside joke from the writers to the fans about a different bird that said Hurley's name in season one, but as far as I'm concerned, the Hurley Bird is definitely not frustrating anymore.