Temptation, all I never wanted -- Old Tom and the One Ring

Speaking of Tom Bombadil in a letter to Naomi Mitchison in 1954 (Letter no. 144, p. 178-79) Tolkien wrote:

Tom Bombadil is not an important person – to the narrative. I suppose he has some importance as a 'comment'. I mean, I do not really write like that: he is just an invention (who first appeared in the Oxford Magazine about 1933), and he represents something that I feel important, though I would not be prepared to analyze the feeling precisely. I would not, however, have left him in, if he did not have some kind of function. I might put it this way. The story is cast in terms of a good side, and a bad side, beauty against ruthless ugliness, tyranny against kingship, moderated freedom with consent against compulsion that has long lost any object save mere power, and so on; but both sides in some degree, conservative or destructive, want a measure of control. but if you have, as it were taken “a vow of poverty”, renounced control, and take your delight in things for themselves without reference to yourself, watching, observing, and to some extent knowing, then the question of the rights and wrongs of power and control might become utterly meaningless to you, and the means of power quite valueless.

Thomas Aquinas said that temptation can come from within or without. External temptation, like that of Adam and Eve in Eden or that of Christ in the desert, is the devil's work. Internal temptation, however, is all our own as fallen creatures out of harmony with God and ourselves. Without setting out to do so, Tolkien shows us in this letter how very much the temptation to claim the power of the Ring arises from within, from the deeps of our desires, whether to save the Shire or to save Gondor, or even to show pity and do good.