Answer: The child of God should make every effort to keep the unity of the Spirit through the bond of peace, (verse 3).
MORE INFORMATION AND/OR OTHER SCRIPTURE REFERENCES:
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."
The "spirit of unity" in God's Children comes from the "unity of the Spirit." All who know and do the Will of God are in the "unity of the Spirit." All believe and obey the same things.