"A self-forgetful person would never be hurt particularly badly by criticism. It would not devastate them, it would not keep them up at night, it would not bother them. Why? Because the person who is devastated by criticism is putting too much value on what other people think, on other people's opinions...When someone whose ego is not puffed up but filled up gets criticism it does not devastate them. They listen to it and see it as an opportunity to change"
Tim Keller, The Freedom of Self-Forgetfulness