Professor Faber is an educated man, a former teacher, and someone who still loves books because he can remember how life was back when books were legal. He remembers the power of the written word, the emotional response reading gave him, and the effect that a book could have on others. However, since he was unwilling to publicly repudiate the new laws making firemen into book-burners, he now lives in shame and misery, knowing that the only chance to save books lies in the past:
"I saw the way things were going, a long time back. I said nothing. I'm one of the innocents who could have spoken up and out when no one would listen to the 'guilty,' but I did not speak and thus became guilty myself."
(Bradbury, Fahrenheit 451, Google Books)
Despite this shame, Faber is scared of the firemen and their laws, and initially is scared of Montag. When Montag expresses his wish to learn about books, Faber relents and speaks of his own past. Faber gives Montag a radio earpiece, showing signs of new courage (he is happy to see that others share his dissatisfaction with modern society) and finally helps Montag escape the city. It is hinted that Faber escapes before the city is destroyed, and that he will join the struggle to build a new civilization.