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. For neither circumcision counts for anything, nor uncircumcision, but a new creation.
Ben Witherington III, Grace in Galatia, 450:
Paul is saying his conversion to a belief in a crucified messiah entailed an enormous transvaluation of values, and an adoption of a new paradigm of what God was really doing in the world, how he was doing it, and therefore what the believer’s life meant. But notice Paul is not simply talking about an experience that happened to him. He also says that the world was crucified to him, by which he means that he believes that the death of Christ on the cross changed the world, it had cosmic effects. Paul has partially addressed this subject when he spoke about what the Galatians had been freed from — the elementary principles of the universe which enslave fallen human beings, and it is attended to even more fully in the later Paulines (cf. especially Col. 2:15 to Eph. 4:7–10). Here Martyn is quite right to stress the importance of this phrase and the mention of the new creation [v. 15] and connect them both with Gal. 1:4.
In Paul’s view the present evil age exists, but has been dealt a deathblow by the crucifixion of Jesus. All of the world’s basic values and assumptions and operating procedures have been put on notice that they are passing away (cf. 1 Cor. 7:31). What really matters are the new eschatological realities brought about because of the death of Christ. In Paul’s view, even the Law, as well as other good things about the material world, are part of the things that are passing away or are fading in glory (cf. 2 Cor. 3). Having lost their controlling grip on a human life when Christ came and died, one must not submit to such forces again, but rather live on the basis of the new eschatological realities. The new age has already dawned and Christians should live by its light and follow the path it illuminates.