Why does Montag remember meeting the old man (Faber) in Fahrenheit 451?
Montag remembered Faber after so long because he offered him one of the first opportunities to hold a true conversation with another human being. When Montag first sees Faber in the park, he notices that Faber is trying to hide something in his coat. What begins as a psuedo-interrogation devolves into a real, natural conversation. They sit together for an hour, and Faber quotes some poetry, which sparks Montag's interest. When Montag goes to leave, Faber gives him his address, which Montag keeps until he visits Faber later in the novel.
This incident made such an impact on Montag because he is so lonely and isolated in his world. His wife Mildred makes no attempt to have a true relationship with him...or anyone else really. Until Clarisse McClellan comes along, Montag has no one to call a friend, and no one with whom to share his thoughts and concerns. Because Faber offered him that, however briefly, he remembers it later when he is under such stress.
As was mentioned in the previous post, Montag recalls meeting Faber in the park and having a pleasant conversation with him. One day, Montag was walking in the park when he saw an old man furtively hide something quickly in his coat. Montag approached the old man, and the two began to have a friendly conversation. Montag and Faber spoke about the weather before Faber admitted to being a retired English professor. After they had spoken for an hour, Faber recited a poem to Montag. Faber then held his hand over his coat and Montag could sense that there was probably a book of poetry underneath. Faber then says, "I don't talk things, sir.... I talk the meaning of things. I sit here and know I'm alive" (Bradbury, 35). Montag remembers the meeting with Faber in the park because it was strange, profound, and pleasant. Montag connected with a kindred spirit that day and took the slip of paper with Faber's number written on it.