Here’s one helpful definition from Tim Keller, pastor of Redeemer Presbyterian Church in New York City:

“The Christian gospel is that I am so flawed that Jesus had to die for me, yet I am so loved and valued that Jesus was glad to die for me. This leads to deep humility and deep confidence at the same time. It undermines both swaggering and sniveling. I cannot feel superior to anyone, and yet I have nothing to prove to anyone. I do not think more of myself nor less of myself. Instead, I think of myself less.”

For lots of great Tim Keller resources (articles, audio sermons, etc), visit Steve McCoy’s Tim Keller Resources page.