In "Biblical Perspective" Larry Grile writes concerning Colossians 3:11:
In the spiritual realm of redemptive grace, human distinctions and divisions are annulled. There are not Greek Christians and Jewish Christians; there are only Christians. In Christ, whether one is circumcised or not does not matter. Whether one is merely a foreigner or is a savage makes no difference. Whether one is a freeman or a slave makes no difference. But Christ is all, and in all. Human distinctions are not erased but are transcended in Jesus Christ. Man's efforts to erase distinctions through a socialist world order are doomed to confusion and failure. Socialism is carnal man's solution to the carnal frictions produced by the human differences in our world. On the other hand, Jesus Christ is everything! Before any of us came to Christ, we were nothing. No matter how low or high we thought we were, Christ exalted us. Now that we are in Christ, we are brethren. Now that Christ is in us, we have no need for social uniformity, for we share a kindred spirit that transcends our diversities (Gal. 3:28).
Source: Building Christian Relationships: Adult Teacher's Insights, page 12.