4 Bible Verses about Harmony

Will two walk together, except they cooperate (collaborate) (have an agreement)?

([Psalm of David]) Behold, how good and how pleasant it is for brothers to dwell together in unity!

May they all be united (in agreement) as one. Just as you, Father, are with me, and I am with you. Help them be united with us! That way the world may believe that you sent me.

Do not be unequally yoked with unbelievers: for what fellowship does righteousness have with lawlessness? Or what communion does light have with darkness?