What did Jack do to the water to make it special? Was it just that Jack had to give Hurley any kind of liquid to give him his powers? I thought Psycho Mother did some kind of incantation over the water before she gave it to Jacob.

Watching last night I thought that was an interesting scene.

Jack goes dippiing into that muddy mudpuddle and I thought "GRRRRR-ROSSS!" However, the water was clear that he gave to Hurley to drink.

So either it was a "gross" oversight of the crew or they were trying to call attention to the fact that the water was muddy and Jack's new "power" made the water clear.

The Mother may have said some kind of incantatin over the water - but Jacob said to Jack, "now, you are like me" and so Jack said the same to Hurley.

Maybe that's all that needed to be said.

Jacob also said something over the water. He held some from the stream in his hands and said something to it and then rubbed it between his hands and let it fall back into the stream then dipped some out for Jack. I too thought it was wierd that Jack didn't say anything over it, but he was the protector for such a short time that I don't know how he would have known what to say.

Maybe the whole thing of passing power was a hoax....maybe power wasn't really passed.

The exchange in the FS between Ben and Hurley suggests that the passing of the power was very real.

On Lostpedia, the basic translation is about how because we believe this drink to be no simple potion or some such thing, it will work.

The clear water deal does seem to indicate that Belief is all that was required.

Seems to be mostly a symbolic thing... the person drinking the water believes it has meaning, therefore it does.

All I could think during both Jack and Hurley's initiation scenes was "...aannnd now you have intestinal parasites!!"

When Jacob gave the cup to Jack after saying his incantation, it seemed real, and at that point, Jack was imortal. But once the light went out, Jack, MIB & Richard were all rendered mortal again & Jack no longer had the power or authority to make Hurley special or live forever. It was reduced to just a symbolic thing of Hurley accepting the job.
My guess is that with Ben's knowledge and experience, they managed to figure out as much of the Island's secrets as possible & united the remaining survivors under their leadership. I'd guess that Rose & Bernard became very infuential advisors to hurley as well. The point was to keep the power of the island from falling into the wrong hands.

I could have this wrong, but if memory serves, Jack did not fill the bottle from the mucky water on the ground. He took it from the clear water streaming from a rock above the muck. I noticed this because I was saying to myself that I hoped he didn't expect Hurley to drink that dirty water, lol.