Locke: why couldn't he have been an uncomplicated bad mutha? Rebuilt god yadda yadda, I suspect -- rebuilt from the feet up.
Allegory alert: the island is acting as a purgatory -- the dead bodies in this episode start off in limbo, and by episode's end, they've passed on, their corporeal forms shuffled off (by fire, in this case [funny, considering the next episode]).
See also: spooky figure that Jack sees, which segues nicely into...
...the figure turning out to be Jack's father, which reemphasizes the lost (heh heh geddit?) histories of the survivors -- the elusiveness and inaccessibility of an antecendent (i.e. the past (i.e. the father)), and ultimately, the disappearance/absence of the father's body. Note, however, that the (empty) coffin rests (finally(?)) in a small pool (read: WATER (read: REBIRTH -- where fire sends the already dead off to wherever, water can give them a new beginning)).
In fact, water plays a dual role that I'd assigned to Locke in Tabula Rasa -- first a destroyer of life (the woman who drowns in the opening scene), then as a savior/giver of life (restoring preggers Claire to good health, providing the scene/ambience for Jack's reconciliation/release of the inaccessible past).
Jack renders my purgatorial reading more relevant: "God knows how long we're going to be here." You damn right, only God knows. COS Y'ALL ARE IN PURGATORY. SUCKERS.
Witness the hand of JJ Abrams, but withering? Forty-seven survivors become 46.