The Two Towers by J.R.R Tolkien (Harper Collins 1991, 2007) pp. 798-803
Think of how many stories that you know in which the hero overcomes the evil against which he stands by means of the way he uses what resources at his disposal, especially the means of violence, to defeat his foes. What matters in all these stories is power and the use of power. That is what makes the Ring so tempting. It is the Ring of Power. The one who possesses it and who has the capacity to use it would gain a power over others that nothing else could give.
And then think of the good that you could do if you had the power to do it. Perhaps you could use your power to protect the innocent and to overcome those who seek to do wrong. This desire, of course, is what lay behind the code of chivalry. Men were trained in the use of arms, the means of power, to the highest degree, but they were also trained spiritually. They were to use their power in the service of the good, the true and the beautiful. They were to defend women and children against harm. They were never to use their power for mere self interest but always for a higher good.
So power in itself is not an evil. If Frodo had not had Sting, the Elven blade that Bilbo had taken from the trolls’ cave on his adventures with the dwarves, then Gollum would have probably killed Sam and then Frodo too. Gollum has survived as long as he has in part because of his cunning but also because he is always prepared to kill and he has killed many times. Neither Frodo or Sam are killers even though they have been in battle. Gollum is.
But there is a fundamental difference between using a sword or any means of violence in desperate need and using them in cold blood. When Isildur took the Ring from Sauron it was in such need. We know little of his history after he took the Ring apart from his unwillingness to destroy it but there is little to suggest that he had become a tyrant. At least not yet. Gollum, on the other hand, gained the Ring by murdering his best friend.
And, crucially, when Bilbo took the Ring from Gollum, he had the opportunity at one point to kill him. Cloaked by the invisibility that the Ring was able to give him he stood behind Gollum who himself was standing between him and freedom. Surely he would have been justified in using Sting to gain his freedom. But he could not kill in cold blood and so he did the riskier thing. He leaped over his crouching enemy and so escaped from the Misty Mountains.
But it was not Bilbo’s need that Frodo was thinking about when he said to Gandalf:”What a pity Bilbo did not stab the vile creature, when he had the chance.” At that moment Frodo was simply afraid of Gollum and disgusted by him. He felt that it would be justifiable, even good, to take Gollum’s life. But Gandalf did not agree.
“Pity? It was Pity that stayed his hand. Pity, and Mercy; not to strike without need.”
And now that Frodo sees Gollum for himself, the half-starved miserable creature in the wild, driven by a hunger over which he has no control, he pities him. Perhaps too, he feels enough of the corrupting power of the Ring himself to understand in a way that no-one else can, apart perhaps from Bilbo, what it means to possess this evil thing. Frodo may be being slowly worn down by the thing that he carries but the goodness with which he has been trained still has power over evil.
And so in Pity Frodo stays his hand. And this makes all the difference. Of course it makes an immediate difference. Frodo and Sam are lost in the wild and without Gollum as a guide they would have starved. And it also makes a crucial difference to the eventual outcome of the story. It is only through Gollum that the Ring eventually goes to the Fire and its destruction; only through Gollum that Sauron is overthrown. And it also makes a crucial difference to Frodo himself. Could he have found healing for all his hurts in the Undying Land if he had murder on his conscience? Perhaps he could but it would have been so much harder.
So it is indeed Pity that indeed “rules the fates of many”, as Gandalf put it. It is a quality in which Gandalf has chosen to be trained and so, crucially, he is different from Saruman. And it is a quality in which he schools three of the vitally important characters in The Lord of the Rings, Aragorn, Faramir and Frodo. Although power plays its part in the final overthrow of Sauron it is Pity and Mercy that make the essential difference. Indeed we could say that it is because Frodo and Sam do not kill Gollum at this moment that Sauron is overthrown.