What the Island Was - Gateway Theory by AVR91

As the finale has shown the flash sideways was infact some sort of purgatory. The Island was not.

If you rememeber back in the season when desmond was shocked full of electromagnetic energy which somehow made him go to the flash sideways which is purgatory

Now we know the heart of the island is where the electromagnetic energy omits from. This meaning that if a person were to come in contact with the heart of the island they would be able to go to purgatory. Thus making the island aa gateway to purgatory. This would explain all the religious markings on the temple and inside caves. Your probably wondering why aren't others able to go to prugatory like Desmond. Well seeing as Desmond had spent a substantial amount of time in the hatch this would mean that he had become immune to negitive effects of electromagatism. Meaning only a select few can use this.

Could this mean that if the island were to be destroyed so would purgatory, which could explain why the light in the tunnel must be protected.