Great artists understand their medium and how it will react to their touch. They know what is and isn't possible with it. They can take what might be considered flaws and turn it into distinguishing features and personality. They know best how to unlock its full potential. They do this through "speaking with" and "listening to" it.
God is the greatest of artists and we are the medium that He uses. He understands us in ways that even we do not fully understand. He asks us to speak with Him, medium to artist, to help contribute to His universal masterpiece. He will unlock from us potential that we would never have realized on our own.