By grace we are saved by faith, not by anything else we have ever done. We were dead by our transgressions undeserving of acceptance but we have been saved " Remember what we were"
In Pauls day groups of people held contempt for one another. Sometimes we can do the same to others if we look down on others not in our group. It can be easy to fall into the mentality of the Jews and the Gentiles. We can label people and de value them. As Christians we can put up barriers to those looking to come into the church. We must remember who we were. Those who we might look down on can also come to Christ. Only Gods grace can save people. Without Christ nobody has anything to boast about. The cross is the place where barriers are destroyed. Christ is our peace and he has broken down barriers between people.
Our shame is that we can re erect barriers that keep people out. What barriers have we got? Having destroyed all barriers at the cross, Christ is building his people and his church. He is at work and he lives in his people. Christ dwells within his people despite what church government they like. Paul calls for an end to rivalries in churches and groups.
Salvation belongs to our God. If we are convicted of putting up barriers... remember Christ
Ephesians ch 1-6