A thought just occurred to me that made me doubt whether it really was Midian's aura that killed Jeruh. All the people who are absorbed in the sword are killed, in a sense, but a part of them lives on. I'm not sure whether those people can undergo change inside the sword but I'm assuming they don't.
When Midian finally meets Jeruh inside the cell at the top of the tower, he tells him he's lost his desire to kill him and doesn't want to see Jeruh die. This wouldn't make any sense at all, if this was the same person who first met Gaius, and murdered Jeruh. The one who killed Jeruh said he had waited a long time, and that he was glad to be ending his life. This leads me to believe that Midian and Jeruh's murderer are not the same person. If this happens to be true, that leaves one burning question...just who the hell was it that killed Jeruh, and why?