From Book 1, Chapter 2, of The Fellowship of the Ring by J. R. R. Tolkien:
Don't tempt me! For I don't wish to become like the Dark Lord himself. Yet the way of the Ring to my heart is by pity, pity for weakness and the desire of strength to do good. Don't tempt me! I dare not take it, not even to keep it safe, unused.
What is the meaning of the phrase in bold?