All that is gold does not glitter,
Not all those who wander are lost;
The old that is strong does not wither,
Deep roots are not reached by the frost.
From the ashes a fire shall be woken,
The wanderer referred to is Aragorn, who was still wandering around Middle-earth before meeting the Fellowship of the Ring in the tavern. 
 This line has become well known and frequently quoted by Tolkien fans as a kind of proverb. 
 In a more general sense, it perhaps suggests that those who are curious and explore life will be rewarded, as opposed to those who are complacent in life.