Many people are speculating that the man in the black shirt from the opening scene is Jacob's brother, so that's what I will refer to him as.
I believe that his brother has the ability to morph into different people. We saw how he (in my opinion) took the form of John Locke to kill Jacob. Also, think about how Christian Shepard would show up in Jacob's cabin no less, and speak "on behalf" of Jacob. Jacob's brother took the from of Christian. Finally, Alex. In the temple, when the smoke monster (maybe the black shirt guy) confronted Ben and took the form of Alex, that was again Jacob's brother.
The one constant in all of these formations of Jacob's brother, is that the physical dead body of that person has been on the island (Locke in the Ajira box, Christian's casket was found, and Alex died on the island).
I believe that his brother has the ability to morph into different people. We saw how he (in my opinion) took the form of John Locke to kill Jacob. Also, think about how Christian Shepard would show up in Jacob's cabin no less, and speak "on behalf" of Jacob. Jacob's brother took the from of Christian. Finally, Alex. In the temple, when the smoke monster (maybe the black shirt guy) confronted Ben and took the form of Alex, that was again Jacob's brother.
The one constant in all of these formations of Jacob's brother, is that the physical dead body of that person has been on the island (Locke in the Ajira box, Christian's casket was found, and Alex died on the island).
