Gandalf's words

Since I have read the Lord of The Rings I have been reviewing some of the points in the book in which events are foretold or simply where great quotations can be found. In watching the movie I was particularly interested in the speech that Gandalf gave to Frodo when they were in the mines of Moria. He told Frodo that he should not wish to hand out fate so freely and that Gollum may have a part to play in the fate of the world for good or for evil, or something close to that. However, when I was going through the chapter in which they travel through the mines in the book, I could not find these words, yet I believe I remember them from somewhere, or perhaps I am just overlooking them. Anyway, if anyone could help me out here or just has some really good quotations they'd like to share that'd be sweet. peace.