Unity isn't easy. Most of us have never learned how to disagree in love, or how to love those with whom we disagree. We're like the poet who wrote:

To dwell above with saints we love,
That will be grace and glory.
To live below with saints we know;
Well, that's another story!

Unity isn't easy. But Jesus not only prayed for it, He modeled it for us. Remember when the disciples came to Him complaining about the people who were preaching and doing signs and wonders in Jesus' name but weren't part of the crowd of disciples? They were ready to run them out of town or call down lightning upon their heads. Jesus told the disciples not to stop them and said, "A good tree cannot bear bad fruit."

Christian unity is not determined by whether we agree with each other about every interpretation of scripture or doctrine or form of church government. Christian unity IS determined by whether we love one another, and whether we reflect the love of God in Christ for the world.