“My prayer for all of them is that they will be one, just as you and I are one, Father – that just as you are in me and I am in you, so they will be in us, and the world will believe you sent me.” John 17:21
The primary reason Jesus prayed for unity is not simply so that we become one, big, happy family of Christians (though he is fully commited to the spiritual and relational nurture of that family). The ultimate purpose of unity is for those outside the family who have no true hope of eternal life.
If you would like more information on the Biblical Case for Chrisitan Unity click here.