Galatians 6:14  But far be it from me to boast except in the cross of our Lord Jesus Christ, by which the world has been crucified to me, and I to the world. 

“In these words the deepest chords of the Pauline kerygma are sounded. Paul speaks here of the cross as the one and sufficient ground on which to build; he also speaks of his own life as of something entirely governed by the cross. Thus, the element of judgment is present also in “has been crucified”. Both the world and the human confidence in it have become manifest not only in their inadequacy but also in their damnableness. The person who lives for the world will together with it be destroyed. By the cross the believer is saved from this destruction. This crucifying of the world and of the self in mutual interdependence means life and redemption for him who has learned to direct his life solely upon the cross of Christ.”  — Herman Ridderbos, Commentary on Galatians, p. 225.