The Fellowship of the Ring
How we cite our quotes:
"[The poem] came to me then, as if I was making it up; but I may have heard it long ago. Certainly it reminds me very much of Bilbo in the last years, before he went away. He used often to say there was only one Road; that it was like a great river: its springs were at every doorstep, and and every path was its tributary. 'It's a dangerous business, Frodo, going out of your door,' he used to say. 'You step into the Road, and if you don't keep your feet, there is no knowing where you might be swept off to. Do you realize that this is the very path that goes through Mirkwood, and that if you let it, it might take you to the Lonely Mountains or even further and to worse places?' He used to say that on the path outside the front door at Bag End, especially after he had been out for a long walk." (1.3.74)
As Frodo sets out on the road to Rivendell with Sam and Pippin, he starts to reminisce about Bilbo. Frodo's early journey mimics Bilbo's adventures in The Hobbit for a time: they both leave the Shire somewhat against their will, at fifty years old, for an adventure that they cannot fully understand at the start. And of course, a lot of the wisdom about travel that Frodo has, he gets from Bilbo's stories.
This speech from Frodo to Pippin underscores the fact that the Shire may seem like a protected and secluded place, but it's still part of the larger world. Even the road from Hobbiton to Buckland is part of the larger Road to Mirkwood. This reminder that the Shire is connected to the rest of Middle-earth, no matter how conservative and private the Hobbits like to be, foreshadows the conclusion of The Return of the King.
"You have read his book!" cried Frodo. "Good heavens above! Is nothing safe?"
"Not too safe, I should say," said Merry. "But I have only had one rapid glance, and that was difficult to get. He never left the book about. I wonder what became of it. I should like another look [...] I kept my knowledge to myself, till this Spring when things got serious. Then we formed our conspiracy; and as we were serious, too, and meant business, we have not been too scrupulous. You are not a very easy nut to crack, and Gandalf is worse. But if you want to be introduced to our chief investigator, I can produce him." (1.5.63-4)
Merry turns out to be a Hobbit of unusual resourcefulness: he finds out about Bilbo's Ring more than a decade before this showdown with Frodo. Rather than blabbing the information, he patiently gathers information and draws in his close friends to find ways to help Frodo without Frodo knowing anything about this well-meaning conspiracy. This small-scale campaign foreshadows Merry's future leadership skills; after all, we know from the Prologue of The Fellowship of the Ring that Merry is going to be the Master of Brandy Hall someday.
Sam sat down and scratched his head and yawned like a cavern. He was worried. This afternoon was getting late, and he thought this sudden sleepiness uncanny. "There's more behind this than sun and warm air," he muttered to himself. "I don't like this great big tree. I don't trust it. Hark at it singing about sleep now! This won't do at all!" (1.6.52)
If the Old Forest episode of The Fellowship of the Ring gives us our first chance to see what the Hobbits are like in an adventure, Sam's response to Old Man Willow proves that he's not particularly vulnerable to mind control. He hears the willow tree singing, but he doesn't topple over, the way Frodo, Merry, and Pippin do. He does his best to keep on going. This bodes well for Sam's participation in the Ring Quest: he's not too sensitive to outside influence, and he's tough as nails.