books on christan unity & division?

[thistle93]

The Bible seems to clearly state that God has only one church (while many manifestations by denominations) and that we who are his church are to be characterized by love and unity. Unfortunately that is often not the case with many parts of the church in this fallen world. Any books you can recommend that are on the "catholic" universal church (apostles creed), the importance of unity of Christians even in our diversity and even though we must contend for the faith we are to do so motivated by love and that not all issues are essentials and can still have fellowship with those we disagree with on secondary issues. Thank you!

For His Glory-
Matthew