apoppin
Lifer
If I remember correctly, neither can Sauron. However, to destroy his ring (the goal) would leave him forever powerless.Morgoth could not be destroyed if I remember correctly, he was merely enchained.
Gandalf was ordered not to use his full powers to fight evil but to persuade men to defy Sauron. (read: Christlike figure).Well, the way I read it, Gandalf isn't as much a 'wizard' as a demi-god/angel type thing. And some of his power comes from the Elf ring that was given to him when he entered Middle Earth from the west. That being said, it's generally accepted that Gandalf didn't show the full extent of his power in Middle-Earth. :Q
The LOTR and Silmarillion delve deeply into religion.