shes gonna explain that more in the 7th book. The only info on that is in the fifth book. Technically you have ot be afraid of death or have un finished dutied on Earth which we dont know that Sirius had any unfinished business. But i doubt that he was afraid o fdeath. But once again thats a mystery and the 7th book is the answer and unfortunately we won't get the answer until 7/7/07. bawling
well ohiluvhp you know my input i haelped come up with the theory but just to add to paliwal_ruppal snape does know about the ring because he helped dumbledore from dying after destroying it dumbledore says in the book so if snape really is loyal to voldy(as one of you put it lol) than voldy knows exactly what harry is up to also dumbledore did say that it was not wise to put a horcrux into a person or animal but if he didnt mean to do it than that explains it . maybe snape suspects something in harry that does remind him of voldy and that is the true reason that he hasnt tried to kill him. and what happens if harry kills voldemort after destroying the rest of the horcruxes than voldy will have to go into harry's body than what happens will someone else have to destroy harry (neville also worked out in the prophesy) or ron or hermione or will harry be able to control someone that evil inside him and/or kill himself all good questions (sorry that was a bit choppy lol)