Frodo asks Gandalf to take the Ring, but the wizard refuses vehemently. With the Ring, Gandalf says, he would become too powerful, and he would inevitably be corrupted like Sauron himself. Even if Gandalf took the Ring simply for safekeeping, the temptation to use it would be too great.
Though someone could start out with good intentions, the Ring would eventually corrupt them. And that is why Gandalf can't touch it. He is afraid that if he did, it would corrupt him and make him just as bad as Sauron since Sauron put so much of himself and his evil into the One Ring.
Gandalf was aware of his purpose and his mandate. In fact, he was offered a chance to break it. Early on, Frodo tried to give him the Ring in Bag End. However, Gandalf knew that if he -- being an extremely powerful Maiar just like Sauron -- had taken the One Ring, he would become no different than the Dark Lord.
The One Ring is too powerful for the already powerful to possess. We've seen Valar-blessed beings in the presence of the One Ring, and we've witnessed their sinister reactions to the power they could hold if they were to take the One Ring for themselves.
At the end of Fellowship of the Ring, Frodo and his companions visit her. Frodo even offers her the one ring. Galadriel admits she has long awaited the chance to seize the powerful token. But, she says, if she took it, she would become corrupted herself and rule over Middle-earth as a beautiful but tyrannical queen.
Galadriel was arrogant and rebellious in her younger years, but she later founded and ruled the kingdom of Lothlórien. She grew to be one of the most powerful Elves in Tolkien's universe thanks to the wisdom she gained throughout her long life.
In The Lord of the Rings, it is said that had Galadriel chosen to use her powers for evil instead of good, she would have been even more destructive and terrifying than Sauron himself. Galadriel was the greatest and most powerful of all Elves in Middle Earth in the Third Age.
The first is that Bilbo is a hobbit, and as such, is particularly difficult to manipulate or corrupt. Hobbits have a natural resistance to the influence of the ring, because they are fully content in their simple lives and have no desires for power or war.
Because of their intense love of the earth, the Ring does not sense hobbits as a threat, which is why they were able to be overlooked and complete the quest.
The Fellowship can't ride eagles to Mordor because of the giant, flying snake-dragon monsters ridden by One-Ring-sensing warrior kings and their half-mile-wide aura of fear.
Over the next 17 years, Gandalf travels extensively, searching for answers on the ring. He finds some answers in Isildur's scroll, in the archives of Minas Tirith. Gandalf searches long and hard for Gollum, often assisted by Aragorn, who eventually succeeds in capturing Gollum.
Because Sauron is a ''free'' Ainu. He has no limitations on the use of his power or on his majestic form. Gandalf was sent by the Valar with restricted powers, both by choice and by natural limitations.
Creating the Ring simultaneously strengthened and weakened Sauron. With the Ring, he could control the power of all the other Rings, and thus he was significantly more powerful after its creation than before; but by binding his power within the Ring, Sauron became dependent on it.
It's a constant reminder to Aragorn of his family history; his hesitation to take the ring from Frodo Baggins (Elijah Wood) is a direct result of Isildur's corruption. Although Boromir ultimately falls victim to the seductive nature of the ring, Aragorn is able to defy his family history and resist his urges.
While the previous 19 rings were crafted with the help of the Elves, the final ring, the 'One Ring to rule them all,' was crafted by Sauron alone; with the ability to dominate the other rings, the One Ring was made with some of Sauron's own power, in order to make it more powerful.
The three Elven Rings were conceived as a means of keeping magic (formally known in J.R.R. Tolkien's Legendarium as the Light of the Eldar) from fading in Middle-earth.
Arwen isn't necessarily dying because of the Ring, but now that she is mortal, she is dying through the slow decaying of time. Arwen also faces the same fate as all those in Middle Earth should the Ring Bearer fail his mission. So in that way, her fate is tied to the Ring.
No, it would have corrupted him. The thing with Hobbits is that they enjoy simplicity and don't seek out fame, power, riches, or glory. Aragorn may have ben able to resist the ring long enough to let Frodo go, but it would have corrupted him eventually.
The Three were untouched by Sauron in their making and were made for preservation so they didn't negatively affect their bearers.
The Hobbits represent small, humble, ordinary people. They don't lust for power or fame, or aspire to do great deeds. Thus the Ring can't corrupt them in the way that it would corrupt Boromir or Galadriel, although it can make them covet it as a possession.
With all this time, it seems Sauron would have found the Ring. However, the simplest as to why he didn't: Sauron had no way of locating his Ring. Because the Nazgûl track Frodo, and the Eye of Sauron "sees" him when he wears the Ring, some presume that Sauron has some way of tracking it.
But in that moment of weakness the ring had the power to blind him to everything else and save it's self from destruction. For the ring to be destroyed it took the end of his adventure and for us the end of the story.
The Elves' fading is said to be a consequence of the darkness Morgoth brought to the realm. The Rings of Power borrows the basic elements of Elves fading away and Valinor offering the path to salvation, but embellishes the rest.
Sauron feared her
The author said that she was the “last remaining of the Great among the High Elves” in the Third Age, and consequently was the one person Sauron must have feared most among all his enemies in the War of the Ring.
Thus, Galadriel's dark form in Jackson's The Lord of the Rings personified what would have occurred had the Lady of Lothlorien given in to temptation and taken the One Ring for herself. She would have succumbed to evil because the Ring was indomitable, even with her power.