what is youre favorite quote from an Arda related book by Tolk? mine is
All that is gold does not glitter
Not all who wander are lost
the old that are strong do not whither
deep roots are not reached by the frost!
From the canon, probably Berens response when Thingol asks where the Silmaril is:
"Even now a Silmaril is in my hand." (p. 184)
That, and the theological overtones in the Ainulindale of the Third Theme of Iluvatar in conflict with Morgoths theme:
"And it essayed to drown the other music by the violence of its voice, but it seemed thta its most triumphant notes were taken by the other and woven into its own solemn pattern." (p. 17)
and two paragraphs later, Iluvatar saying, "And thou, Melkor, shalt see that no theme may be played that hath not its uttermost source in me, nor can any alter the music in my despite. For he that attempteth this shall prove but mine instrument in the devising of things more wonderful, which he himself hath not imagined." (Ibid.)
A lot of folks want suffering to be "justified." I've found nothing better than the above.
Yours got me a perfect score on the AP English test though, so it has a special place in my heart (note to students: LotR, if not all of the canon, is a "work of recognized literary merit" by the standards of the College Board, something about which I had great trepidation at the time.)
From ANY Tolkien work, probably Mandos words in his doom that "Great is the Fall of Gondolin" 'cos Gondolin rocks (but that's "Tolkien Aprocrypha" since it's LT1, 1986, can't find a statement on which edition, but I'm guessing second or third, p. 167.)
All other qoutes from the 1977 edition of The Silmarillion. (There, it's annotated, be happy.)
I really liked the words of the terrible Oath. It was a very powerful one.