Because of what Paul has been writing to the Ephesians, he tells them how they should live their lives as believers and again emphasizes that believers are to agree with each other.
Here Paul speaks of "peace" as if it were a bond that ties people together. This is a metaphor for being united with other people by living peacefully with them. AT: "to live peacefully with one another and remain united as the Spirit made possible" (See: rc://en/ta/man/translate/figs-metaphor]])