It discusses humanity's condition in original sin (the state of separation from God) and is set in the context of Ephesians 1:19-21. Ephesians 2:13-16 deals primarily with reconciliation (which presupposes estrangement).
The prayer begins with a doxology and ends with one. (1) Ephesians 2:13-16 is a significant part of the author's prayer that extends from 1:3 to 3:21. Although some scholars believe that Paul wrote the letter, others believe that he did not.
The letter to the Ephesians is addressed to Gentile believers in a multiracial and trans-national church. What are those barriers? To what nations do they refer? Are those barriers still relevant for people living in the third millennium? In essence, are the barriers still broken down, or have we erected new ones? In Ephesians 2:13-16, the author refers to erected barriers that are between nations and that were broken down by the death of Christ.