Basicly it's saying that Pencil #2 and Pencil #1 got into a serious fight or something (whatever fits the problem) and so Pencil #2 writes "listen" as if he/she wants Pencil #1 to hear what he/she is trying to explain or say that had happen, instead Pencil #1 erases "Listen" as if he/she has heard enough and doesn't want to hear anymore, not wanting to give Pencil #2 a chance.
It is an analogy. Consider the pencils as people. The pencil writing is the "speaking." The pencil erasing is the one refusing to listen. This is shown by this pencil erasing what the first pencil wrote. Think outside the box.