Most churches want unity. Very few preach that they want to be disconnected from other churches and be on their own. But there have been some churches that have pushed for their church’s doctrinal stance or experienced a new found lack of connection with the other traditions, regardless of past closeness.
One example of this is a recent issue I have seen was between a Baptist Church and a Methodist Church. The Methodist Church held sunrise service every Easter for a long time under a male pastor. Everyone was invited. But one day, the male pastor was moved and replaced by a female pastor. The Baptist church was SBC in affiliation, which meant that they did not accept female leadership. The Baptist church decided to not attend the community sunrise service while the woman was over the other church.
Though this seems to be a heavy issue among Baptists, the deeper issue here is a church basing itself on its doctrine and then making its doctrine the basis of the Church Universal. The problems here are infinite, but the core issue is that one party is shutting down the opportunity for discussion, because no matter what side of the issue you stand, the discussion has never been resolved, and to stop it is to be unfaithful to God and the Church.
There are reason people have their opinions, but what makes a discussion nothing more than mudslinging is the lack of an open ear and comprehension. All sides have been guilty of this pursuit. It is not that we cannot be honest, but questions and opposition should be allowed. The church is a challenging group and we ask the questions to each other. We stand in opposition to each other but are called to learn to live life together.
If you are tempted to shut down the other side and have your view prevail, pause and think about your place in the Kingdom. Chances are that you see yourself as a power. One look at passages like John 13 shows that Jesus, the true leader, exemplified being good to those who are on disagreement with us (like Peter) or even those who we think are enemies (like Judas). We should at least be treating other denominations like this since we only be disagreeing with them (hopefully we are not thinking that we are enemies).
What is your church affiliation? Does it keep you from loving other brothers and sister in other denominations? Why? Are you willing to let Christ determine your interaction?