It seemed to Frodo then that he heard, quite plainly but far off, voices out of the past:
What a pity Bilbo did not stab the vile creature when he had the chance!
Pity? It was Pity that stayed his hand. Pity, and Mercy: not to strike without need.
I do not feel any pity for Gollum. He deserves death.
Deserves death! I daresay he does. Many that live deserve death. And some die that deserve life. Can you give that to them? Then be not too eager to deal out death in the name of justice, fearing for your own safety. Even the wise cannot see all ends.
“Very well,” he answered aloud, lowering his sword. “But still I am afraid. And yet, as you see, I will not touch the creature. For now that I see him, I do pity him.” – The Lord of the Rings: The Two Towers, Chapter Twelve (Chapter One of Book Four): The Taming of Sméagol by J. R. R. Tolkien