Romans 12:2 says: do not conform to the pattern of this world, but be transformed by the renewing of your mind. The word for conform implies being pressed into a mould from the outside. The word for transform is where we get metamorphosis. One is passive and happens to you. The other is active and requires intentional choice. What you fill your mind with shapes the kind of person you are becoming — slowly, below the level of notice, until one day it is obvious.