This quote is from Part II of Farenheit 451 in which Montag seeks Faber's help in getting his bible reprinted so that he can turn one copy over to the authorities if he needs it. While he and Faber talk at the old professor's home, the curious Montag asks his new mentor to explain to him that which he reads. Then, Faber explains the what Montag needs to learn is truly around him; it is only that books facilitate knowledge by recording the events and experiences of life. And, when people read books, they devote time to thinking while they read and afterwards. However, in their society, people are not allowed this time because they are subjected to constant stimuli from technology that distracts and clouds their thinking. Faber contends that people need the time to learn and the right to use what they learn in order to change society. They need
a rich texture of life, leisurely enjoyment, and freedom to act on one’s ideas—all values despised by the materialistic society around them.
Then, because people cannot have this "rich texture of life," they cannot construct, or "build," they destroy: "Those who don't build must burn...." Throughout his narrative, Bradbury repeats the words "burn" and "burning" in order to convey the destructiveness of materialism and technology that prohibits and eventually eradicates the finer arts and matters of the heart. For, like his character Faber, Bradbury himself once commented, "You don't have to burn books to destroy a culture; just get people to stop reading." Those who do not facilitate learning, knowledge, and independent thinking and the freedoms that accompany thought, must ultimately destroy a culture.