"Harmony with one another" ("the same
mind"--KJV) literally means "thinking the same
thing toward one another." It means "to be in
agreement, to live in harmony." One version of the
Bible (Twentieth Century New Testament) translates this as
"In your relations with one another, cultivate a spirit of
harmony." Harmony equals unity:
Romans 15:5-6: "May the God Who
gives endurance and encouragement give you a spirit of unity among
yourselves as you follow Christ Jesus, so that with one heart and
mouth you may glorify the God and Father of our Lord Jesus
Christ."
1 Peter 3:8-9: "Finally, all of
you, live in harmony with one another; be sympathetic, love as
brothers, be compassionate and humble. Do not repay evil with
evil or insult with insult, but with blessing, because to this you
were called so that you may inherit a blessing."