Think about a window and its purpose. Now imagine a house with one window in it. Holden is inside the house, ignoring a storm rage outside through this window. As he gets older, the window gets larger and the storm harder to ignore. By the time Holden is 18, the house has diminished completely and has been replaced by glass on all sides. The storm is about to break the window, which will leave Holden exposed.
The house represents Holden’s childhood, while everything outside of it is the adult world. The storm characterizes Holden’s fear of growing up, but he need not face it as long as he is sheltered inside his childhood. The window, however, represents the glimpses of adulthood that he has faced so far. As we get older, our childhood flees farther from our grasp, and it gets much harder and eventually impossible to ignore that we will one day no longer be children.
This concept is like a window. A window allows us to see everything outside without being subjected to the vulnerability that accompanies the act of experiencing it. And as we all should know, it’s impossible to live inside a house indefinitely; at some point, we all need to go outside.
But this is precisely what Holden is attempting to do — he’s trying to ignore the fact that he is two years away from being an adult (in today’s legal definition, anyway) by surrounding himself with thoughts that keep him emotionally in the past.
In this sentence, “phonies… coming in through the goddamn window” is not only a way of expressing how many people Holden believes are phonies, but it is also a metaphor that expresses how those he believes to be phony (ie. mainly adults) are infiltrating his inner sanctum of childhood.
As you read more mentions of windows, keep this imagery in mind. Who is coming through Holden’s window? Who is going out? Where are the windows?
Hopefully this explanation was not too confusing!
To help improve the meaning of these lyrics, visit "The Catcher in the Rye (Chap. 2)" by J.D. Salinger and leave a comment on the lyrics box